Marco Polo

Marco Polo (born 1252) was a Venetian trader and explorer who travelled with the First Doctor and his companions.

Biography
Polo, with his father and uncle, left for Cathay in the year 1271. By his twenty-fifth birthday in 1277, he had come into the service of Kublai Khan. In 1287, Marco, his father and uncle asked the Khan to be permitted to return home. The Khan refused.

Polo encountered the First Doctor, Ian, Barbara and Susan on the Plain of Pamir in 1289 and promptly seized the TARDIS as a gift for the Khan. He hoped it would be sufficiently impressive to buy his way out of the Khan's service so he could return home. The Doctor and his companions were forced to make a long overland journey with Polo, during which time they got to know him well. He helped prevent an assassination attempt on the Khan's life by the Mongol warlord Tegana. Following this, Marco returned the TARDIS keys to their owners to allow their escape as Tegana's body was removed. Barbara claimed that she knew that Polo would see Venice again. (TV: Marco Polo)

Iris Wildthyme once held a party in Hobbe's End in 1972 which Marco Polo attended. (PROSE: From Wildthyme with Love)

The Doctor remarked to Susan once that they had saved Polo's life numerous times. (AUDIO: The Alchemists)

Alternate timeline
In an alternate timeline, Polo purchased the Pandorica. As always, an Auton reconstruction of Amy Pond's fiancé, Rory Williams, accompanied the box. (TV: The Big Bang)

Minor references
Astrolabus claimed he had an appointment in Cathay with Marco Polo. (COMIC: Voyager)

Behind the scenes
Marco Polo offers a clear example of how Doctor Who universe history differs from real world history. According to real world history, Polo was born in 1254. However, the first episode of Marco Polo explicitly tells us that he turned twenty-five in 1277, meaning that in the Doctor Who universe Marco Polo was born in 1252.