The principles behind the jet engine have been understood for thousands of years. The first precursor to the modern jet engine was invented by Heron around 150 BC. Heron's Aeolipile created a mechanical force from steam pressure by heating water up in a ball with two opposing bent tubes attached; steam exiting through the tubes created a reaction force that spun the ball. http://www.smith.edu/hsc/museum/ancient_inventions/steamenging2.html

Reaction type propulsion was again seen in the 1200AD with the advent of the rocket in China.

Italian engineer Giovanni Branca invented the first impulse turbine in 1629. Pressurized steam exited a closed tank through a nozzle, which was directed towards a turbine. The turbine then turned the gear system that operated Branca's mill.

http://home.att.net/~SpaceWeb/SPSM5900/S5900_week1notes.htm

In 1687, Gravensade attempted the creation of a carriage driven by steam power. Pressurized steam leaving a closed vessel was directed through a nozzle in the opposite direction of desired movement. Unfortunately, the steam did not produce enough power to move the carriage.

http://home.att.net/~SpaceWeb/SPSM5900/S5900_week1notes.htm

The first patent for an engine using that used the thermodynamic cycle of a modern gas turbine was given in 1791 to Englishman John Barber. His engine included a compressor, a turbine, and a combustion chamber.

http://home.att.net/~SpaceWeb/SPSM5900/S5900_week1notes.htm

The modern jet engine was engineered simultaneously by Hans von Ohain in Germany and Frank Whittle in England in the 1930s. Frank Whittle began his career as a design engineer in the Royal Air Force. Frustrated with their unwillingness to support the development of the reaction turbo jet, Whittle formed Power Jets, Ltd in 1936. Whittle's company was successful and contracted with Air Ministry in 1939 to produce a flight engine. The first of Whittle's jet propelled planes flew at 400mph with a thrust of approximately 1000 pounds. One of Whittle's biggest obstacles in the development of his engine was the need for strong metals that would withstand high temperatures. Included in Whittle's first engine were an impeller-type compressor, a multiple-can combustion chamber, and a single stage turbine wheel.

After Hans von Ohain demonstrated a model of a gas turbine engine in 1936, he received unlimited funding from the German government. This allowed him to proceed quickly with his designs and the first German jet propelled flight occurred in 1939. The centrifugal flow turbojet on the first jet propelled plane produced approximately 1100 pounds of thrust. von Ohain later developed an axial flow engine, the beginning of what is now the standard for gas turbine engines.

The first jet engines in the United States were designed after Whittle's first engines. While GE produced the first jet engines in the United States, it was Westinghouse Corporation which developed it's own engine, including the development of the axial compressor and annular combustion chamber which are still being used in turbine engines today.

The military has had the greatest role in the development of jet engines, with the first jet engines funded in anticipation of World War II and further developments in the jet engine greatly increased at the onset of the Cold War. The development of the jet engine has required the redesign of airplanes to accommodate greater speeds and new degrees of stress. The 60 years following the advent of the modern jet engine have seen many advances including the propulsion of Apollo 10 to the record speed of 24,790.8 miles per hour.