The tough farming conditions in the Red River Valley of western Minnesota and eastern North Dakota has spawned many of the most significant advancements in farm machinery over the past century. According to David Meyer, co-founder and chairman of the Titan Machinery equipment dealership group based in Fargo, N.D., the most important innovations originating from the region include 4WD equipment, the air seeder, tracks on tractors, combines and the skid steer.

Of those on Meyer’s shortlist, skid steers have proven to be the most versatile with wide ranging applications. The skid steer was the brainchild of brothers Cyril and Louis Keller and was originally developed to clean poultry barns. Ensuing decades demonstrated that its applications have exploded far beyond its original purpose. From agriculture to construction to landscaping and snow removal to warehousing and foundries, today’s skid steer is used in a myriad of applications and industries. Some say it launched the compact equipment industry.

Often referred to today by its brand name as the “Bobcat,” the original machine that evolved into the Bobcat was called the Keller Self-Propelled Loader (U.S. Patent No. 3,151,503). 

Cyril Keller (1922-2020) & Louis Keller (1923-2010

Keller Mfg. & Welding, Rothsay, Minn.; Melroe Mfg. Co. and Bobcat Co.

Founded1947

Position: Founders

Claim to FameInvented the skid steer, launching the compact equipment industry.

They Wanted to Be Farmers. The Keller brothers grew up near Tintah, Minn., helping their father and grandfather on the farm as well as repairing and fabricating equipment in their grandfather’s shop. Their formal education extended only through the eighth grade. At the start of World War II, Cyril enlisted in the Navy and Louis was drafted into the Army. 

At the end of the war the brothers returned to Minnesota. While they would have liked to continue farming, “It was too expensive to start,” says Louis’s son Joe Keller. So, Louis went to work at a foundry in Fergus Falls, Minn., and Cyril began working for an implement dealership in Elbow Lake, Minn.

Recognizing his mechanical talents, one of the foundry owners encouraged Louis to start his own business and suggested that he set up shop in Rothsay, Minn. “In 1947, Louis rented a small building for a shop, moved his family to Rothsay and started Keller Welding & Mfg.,” says Joe.

He goes on to explain, “In addition to repairing and fabricating items for area farmers, Louis also would design and build his own products.” For example, after watching a demonstration of a snowplow, Louis decided he had a better idea. During the winter of 1948 he designed and manufactured a snowblower that could be attached to the front of a tractor, which proved highly successful. He followed this up with a walk behind snowblower in 1949. 

The Farmhand Co. was licensed to build the tractor size snowblowers, but Louis kept the right to build the walk-behind blowers. “The snowblower was Louis’s first major creation and his design is the same basic style still used today,” says Joe.

A Unique Challenge, A Unique Solution. By 1953, Louis had more business than he could handle, so he asked his brother Cyril to join the business as an equal partner. It was shortly thereafter when a frequent customer approached the brothers looking for a solution to a unique problem. 

Eddie Velo was a pioneer in the turkey industry, utilizing large two-story barns. At the time it was believed he had 5 farms and 10 barns. Removing manure from the barns had become a major headache for Velo because once the turkeys were shipped to market, he had only 3 days to clean out the barns and put down new bedding. 

One day Eddie stopped by Keller Mfg. and shared how difficult it was finding the labor required to get the barns ready for the next flock of turkeys. He said he needed something that could operate in very tight spaces and light enough to operate on the second floor of the barns. Louis and Cyril said they would think about it, but at the time they were too busy to put any time into it.

bobcat-m440-prototype-louis-keller-1962-jpg.jpg

Louis Keller operates the first M440 prototype, which featured a more robust design and was the first to have closed drive compartments and double-acting hydraulic lift cylinders. Joe Keller

“Shortly after things slowed down, Louis and Cyril came up with a machine concept that could potentially turn on a dime/within its own length and sketched it on a large piece of cardboard,” explains Joe. Velo liked the idea and agreed to pay for the materials needed and Cyril and Louis would invest their time to build the first machine. 

Joe says, “That way if it didn’t work, they would all be out of their investment in this team project. If it did work, Eddie would pay for their time to build it but not development time.”

It took only 6 weeks from the time of this agreement until the first one was up and running. “Testing started immediately on the turkey farm, and it went well,” says Joe. “They discovered some things that needed to be made stronger and continued to make improvements.”

For example, the first units ran on three wheels, one being a caster wheel on the back that allowed the machine to turn. But it broke and needed to be made stronger. To steer, the front wheels were designed so one wheel could go forward while the other would go in reverse. They were controlled by two hand levers; it had no steering wheel and utilized a belt and chain drive system that didn’t require any shifting. The bucket was controlled by two foot pedals. The machine utilized a 6-horsepower motor.

A couple final improvements were switching out the belts, which would slip, to the patented all chain and clutch drive system. They also upgraded the manure fork tines from steel rods that would bend to heavier steel rods made from bars from the town’s old jail. They didn’t bend.

Velo was satisfied with the machine’s operation and the Kellers sent an invoice for the materials and their fabrication time to him Feb. 4, 1957, and he paid for this first machine March 7, 1957. “They didn’t imagine that the first Keller Self-Propelled Loader would be the start of today’s entire skid-steer and compact equipment industry,” says Joe.

Meeting the Melroes. At the time, the brothers’ uncle, Anton Christianson, owned an Allis Chalmers dealership in Elbow Lake, Minn., which sold Melroe Co.’s well known windrow pickups and harrow weeders. At this time there weren’t many farm equipment manufacturers in North Dakota and Melroe Co. was the largest. The founder of the company, E.G. Melroe had passed away in 1955. The company was then taken over by his four sons and son-in-law. One of the four Melroe brothers, Les Melroe, stopped by the dealership one day, around mid-summer of 1958, for a visit and Christianson told him his nephews had something he should look at. 

By that time Louis and Cyril had built 6 more Keller Loaders. When Les Melroe stopped by for a demonstration, they still had one loader that remained unsold. Following the demo, Melroe Co. invited the brothers to display their machine at its booth during the 1958 Minnesota State Fair in St. Paul. 

The high level of interest the revolutionary loader garnered during the event led Melroe Co. to offer the brothers an employment opportunity. Louis and Cyril would become Melroe Co. employees and work at the firm’s Gwinner, N.D., facility, to be part of a team to improve on the design of their Keller Loader. Melroe Mfg. was already a successful company producing E.G. Melroe’s well known windrow pickups and harrow weeders. 

Joe says Cyril then took one of the six and hit the road to sell it. “Cyril never came back,” so to speak. He finished the rest of his career working along with the Melroe sales team selling, setting up dealers and training salespeople how to run a Bobcat. In an interview prior to his death, Cyril said, “The hardest thing about the early sales was that it had no steering wheel. It was the hardest thing for them to learn. We had to take the time to show them that each hand lever did one thing and each foot pedal did one thing. You could run the bucket, stop, reverse and brake-all with the hand levers and foot pedals.”

Meanwhile Louis and the Melroe team continued designing new models and making changes, many of which were based on customer input he received through Cyril and the entire Melroe sales force. 

In 1961, after slow sales and much investment from Melroe Mfg., a M200 three-wheeled model was modified to create the first 4WD skid steer loader and was dubbed the M400.

With more significant investment from Melroe Co., by 1962, Louis and Cyril along with the Melroe team lead by Cliff Melroe developed an improved 4WD model. This improved model was dubbed M440 and replaced M400 unit. “In addition to a more robust design, the new model was the first to have the enclosed drive compartments and double-acting hydraulic lift cylinders,” says Joe. 

“An additional significant change to the M440 was it would have the necessary 70/30 back-to-front weight distribution needed to make the skid loader turn easily,” he explains. “Without a load, the front end would skid easily and with a full load the rear would skid easily. This made the M440 the first true skid-steer loader.”

Becoming the ‘Bobcat.’ Once the 440 was developed it opened new market opportunities and thoughts of needing a name for the product. During a meeting with Flint Advertising in Fargo the idea of Bobcat came up for a name. During that meeting it was pointed out that the bobcat animal was “tough, quick and agile.” The group decided this was a perfect description of the skid steer.

It was also decided the new Bobcat would be painted white. During the meeting it was pointed out that sales of the skid steer to the fertilizer market were growing and they saw strong potential for increased sales to the dairy industry. This helped to determine that the equipment would be painted white. “The group at the meeting figured the white color would help hide the fertilizer dust while demonstrating cleanliness for the dairy market.”

A 'Transformational Product.’ Howard Dahl, a member of the Melroe family, calls the Bobcat skid steer a “transformational product” and the “Swiss Army Knife”

 of machinery. Dahl knows what he’s talking about when it comes to equipment breakthroughs. His companies — Concord and Amity Technology — have developed the air seeder, sugar beet harvesting equipment and soil sampling equipment.


“It's my personal belief that these two brothers should receive the Nobel Peace Prize for this machine … The unfathomable amount of man hours and backbreaking labor this machine has saved mankind is a true blessing to the human race the world over.…”


“Before the Bobcat, a lot of material handling around the farm consisted of a wheelbarrow and a shovel,” says Dahl. Today, he estimates there are between 300-400 attachments that can be used with the skid steer, making it the most versatile machine for farming, construction and dozens of other industries. It is also estimated that more skid-steer loaders are used in the construction industry than any other single piece of equipment.

Joe Keller adds that applications for the Bobcat have grown way beyond what the Keller brothers ever dreamt.

Accolades Abound. The inventiveness, creativity and drive to help customers led the Keller brothers’ and the Melroe team to create one of the most important machines of the 20th century. 

Since Cyril and Louis introduced the first Keller Self-Propelled Loader in 1957 and worked to develop the modern skid steer, literally hundreds of thousands of the machines have been manufactured and sold around the world. Today, dozens of manufacturers produce skid-steer loaders under various brand names. Nonetheless, the name “Bobcat” remains the most recognized identifier of skid steers today. 

The inventiveness and wide use of this equipment has been widely acknowledged. The Assn. of Equipment Manufacturers inducted Cyril and Louis Keller into its Hall of Fame in 1999. In 2004, they were inducted into the Minnesota Inventors Hall of Fame. This was followed by their induction into the National Inventors Hall of Fame in 2023. 

Since 1997, Joe Keller and his sister, Marilyn Loegering, have worked diligently to preserve their father and uncle’s role in Bobcat’s history. “Winning the NIHF (National Inventors Hall of Fame) award last year has done much more in preserving their history. Now the Farm Equipment Shortline Legends award will do even more,” says Joe Keller.

Genius & Humility Combined. Accolades aside, the human side of the Keller brothers’ story is as big a part of their legacy as was their inventive genius. 

During a video interview conducted while they were still alive, Cyril commented, “God gives everyone a gift and we used ours to help people do things better. My brother and I had a good relationship. I listened to him and he listened to me. If I came up with something and Louis thought he could make it better, that’s the way it went.”

And looking back, Louis expressed his feeling about what they had accomplished by simply saying, “It makes you feel good when you hear about how many people are enjoying it and benefiting from it.”  


Read about the other Shortline Legends

Howard Martin

Richard Unverferth

Al Myers

Cyril & Louis Keller

Wilf Degelman