It’s a wind instrument from the Brass family
considered as the lowest in a band or orchestra

Very old!
      The most ancient type of tuba was a Roman buccina used as an infantry bugle employed to sound the morning and evening watches, as well as at military funerals.
       It had a spiral form. Adolphe Sax improved the brass instruments. He made a family of instruments called saxhorns by 1845. The deepest became known as the tuba in orchestras. It also had three valves.
Phasey, a Guardsman, further improved the tuba in the 1870's. He widened the bore and changed other aspects. It became known as the bombardon, or tuba.