Field plows used Holt farm tractors, which were the ancestors of bulldozers. Tractor adaptability in soft ground for logging and road construction was an important factor in the development of the armored tank during World War I.

Draftsman J. Earl McLeod and young farmer James Cummings created the bulldozer's initial designs in 1923. A replica of the first bulldozer is on exhibit in the city park in Morrowville, Kansas, where the two constructed it. Cummings and McLeod applied for U.S. Patent #1,522,378 on December 18, 1923, and it was granted on January 6, 1925, for an "Attachment for Tractors."

Tracked vehicles, like the Caterpillar 60, were widely used by the 1920s. In the 1940s, automobiles with rubber tires were introduced. These tractors had a big, thick metal plate up front that they could use to dig canals, raise earth dams, and do other earth-movearthmovingater; the blade developed a curved form. Some early variants had no cabin, and the driver sat outside on top. Bulldozer blades come in three primary varieties: a U-shaped blade designed for transporting and pushing material over extended distances, a straight blade for dispersing and "knocking down" dirt heaps, and a brush rake for clearing brush and roots. By 1929, these attachments—made at home or by small equipment manufacturers—were made for trucks and tractors with wheels and crawlers.



Bull-graders do not appear to have gained widespread acceptance before the mid-1930s. By the 1940s, large and small contractors alike favored them as excavation machines because they added power downforce from hydraulic cylinders, which replaced the blade's weight. At that point, the term "bulldozer" referred to the complete vehicle, not just the attachment.
The need for machinery suitable for ever-larger earthworks led to the development of more extensive and more potent bulldozers. Large tracked-type earthmoving was produced by companies including International Harvester, BEML, XGMA, Euclid, Allis Chalmers, Liebherr, LiuGong, Terex, Fiat-Allis, John Deere, and Komatsu. GG.R.LeTourneau and Caterpillar produced giant bulldozers with rubber tires.
Over time, bulldozers became increasingly advanced. Some improvements include drivetrains similar to those found in cars, which use an automatic gearbox rather than a manual one like the early Euclid C-6 and TC-12 or Model C Tournadozer, blade movement controlled by electric motors or hydraulic cylinders rather than the cable winch/brake found in the early models, and automatic grade control. Hydraulic cylinders made automated controls, finer blade manipulation, and the application of downforce possible.




Installing GPS equipment on bulldozers, such as those made by Trimble Inc., Topcon Positioning Systems, Inc., or Leica Geosystems, is a recent development that allows for precise grade control and (perhaps) "stateless" construction. In response to the numerous and frequently contradictory claims made regarding these systems, The Kellogg Report released a thorough analysis of all the manufacturers' systems in 2010, analyzing over 200 features specifically for dozers.

In the U.S., Caterpillar is undoubtedly the most well-known manufacturer of bulldozers, having built a solid reputation for producing dependable, vital equipment. JCB, John Deere, and Komatsu are competitors nowadays. Despite starting out as modified farm tractors, these devices evolved into the backbone of large-scale civil construction projects and were adopted by military construction units across the globe. The most well-known model, the Caterpillar D9, was also employed to destroy enemy structures and remove mines.

Although these had been around since 1929, they were referred to as "bull grader" blades, and it does not seem that the word "bulldozer blade" became popular until the middle of the 1930s. The term "bulldozer" no longer only refers to the attachment but the entire machine. These days, "bulldozer" is sometimes abbreviated as "dozer."

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