The picture of Queen Victoria is a still of Pauline Collins in character from Tooth and Claw (2006).
At one point The Doctor gives a poetic account of the Ice Warriors and Bill replies "...like The Vikings (1958)." In the original script for The Ice Warriors: Episode One (1967), they were intended to be futuristic Vikings with bionic armor before being changed to reptiles.
This marks the first appearance of a female Ice Warrior.
'Empress of Mars' is the ninth episode of "Doctor Who" that is written by Mark Gatiss. At the time of its first airing, Gatiss became the longest serving writer of Doctor Who since the revival, his first contribution being the third episode of Series 1, The Unquiet Dead (2005).
Friday tells Irraxa that they have slept for 5000 years. Presumably he meant 5000 Mars years, which would equal about 9500 Earth years.