Short answers, pulled from the story.
Trumpets began to be used as musical instruments only in the late 14th or early 15th century. Before that, trumpet-like instruments were used as signaling devices in battle and religious contexts, with examples dating back to the 2nd millennium BC.
The most common B trumpet has a tubing length of about 1.48 meters. Its pitches sound a whole step lower than written, making it a transposing instrument.
Tutankhamun was buried with two trumpets, one made of bronze and one of silver, in his grave in Egypt. These instruments are among the earliest physical examples of the trumpet, dating to around 2000 BC or earlier.
The Golden Age of the natural trumpet refers to the Baroque era, when specialist trumpeters developed the upper clarino register of the instrument. This period saw a large body of virtuoso music written specifically for skilled trumpeters. Interest in the natural trumpet was revived in the mid-20th century.
Joseph Haydn wrote his Trumpet Concerto in 1796 for Anton Weidinger, who had developed the first successful keyed trumpet capable of playing chromatically in the 1790s. The concerto startled contemporary audiences with its novelty, especially its stepwise melodies in the instrument's low register.
The trumpet family ranges from the piccolo trumpet, which sounds an octave above the standard B instrument, to the bass trumpet, which sounds an octave below. Other types include C, D, and E trumpets, the pocket trumpet, the herald trumpet, the flumpet (designed by David Monette in 1989), and rotary-valve trumpets used in German and Austrian orchestras.