The series was produced by the popular British animation studio Tony Collingwood Productions Limited in association with Warner Music Vision and Europe Images, and was originally shown on the BBC as part of their children's block CBBC.
Based on an idea by Jan Younghusband, Oscar's Orchestra was designed to inspire children with the delights of classical music and incorporates famous orchestrated works from the great composers in each episode such as George Frideric Handel, Johann Sebastian Bach, Ludwig van Beethoven, Wolfgang Amadeus Mozart and Frédéric Chopin.
Other human characters include the townspeople of Old Vienna, who are on Oscar and his Orchestra's side, Thaddeus's nephew Tobias Vent, who seems to reciprocate Rebecca's feelings for him and joined the Orchestra's side during the episode Star Crossed, Thaddeus's Spanish Vice Dictator, Big Sam the boss of Chicago, Ali Babwa and his forty thieves, Rheena, who's an opera singer, Thadius's old piano teacher Kevin, who was one of the only people to treat Oscar as a friend when he was Vent's piano, Thaddeus's mother Thadweena, who is the former ruler of the world, and William Tell and his father William Tell.
Other characters in the show include Reg the bumblebee, Plutons (aliens on Pluto), an alien from Jupiter, Martians(aliens on Mars), mechonomen, or robots, created and programmed by Goodtooth for the purpose of destroying Oscar's Orchestra, giant tunnel rats and the Rat King, who allied with Thadius Vent in exchange for smelly cheese and live in the underground tunnels underneath Old Vienna, the Mountain King who lives in the mountain underneath Thadius Vent's castle, and the inhabitants of Count Jugula's castle.
Johann Sebastian Bach, Ludwig van Beethoven, and Wolfgang Amadeus Mozart have all appeared in the show as humans in the past, when Oscar and his Orchestra go back in time via Eric.