The trombone is essentially a big slide trumpet- in fact, the name trombone means in Italian "big trumpet." While there are unverified stories dating the trombone back to the Spartans in 685 B.C./ the first authenticated trombone arrived in the 14th century with the first use of the tuning slide. (The trombone slide is simply an elongated, easily operated tuning slide.) 

Until the origin Olds trombone patents of 1912, the trombone had advanced little in mechanical perfection. Unwieldy slides greatly inhibited the free flow of music they were capable of producing. F.E. Olds, the master mechanic, realized the essence of the trombone was the facility of the slide. In applying sound mechanical principals to slide design and a more conical design to the air column, he ushered in the new era of the trombone.

The addition of the F tubing with rotary valve on a bass trombone to fill the five semi-tone gap between the E below the staff to pedal Bflat was first done by Adolph Sax. While this is considered a feature of the bass trombone, its use in the tenor instruments is not unknown.