Cyrus Sylvester Frederick Christie is an English-born Irish professional footballer, who plays for Derby County and the Republic of Ireland national football team as a defender.

Born in England, Christie was eligible to represent the Republic of Ireland through his grandmother from Dublin. He is the great great grandson of former Shamrock Rovers player of the 1920s, Patrick Malone. In October 2014, Ireland manager Martin O'Neill reached out to Christie over representing the Republic of Ireland having been impressed with his performances for Derby at the beginning of the 2013–14 season following his move from Coventry. On 10 November, Christie was called into the Ireland squad for a UEFA Euro 2016 qualifying match against Scotland, and a friendly against the United States.

On 18 November 2014, Christie made his international bow for the Republic against the United States, in a 4–1 win at the Aviva Stadium, with Martin O'Neill praising the performance of Christie on his debut. He scored his first goal for the Republic of Ireland against Gibraltar with his second appearance, his first in a competitive game for Ireland in Faro, Portugal against Gibraltar (Gibraltar's home ground for international competition). On October 8th 2015 he was selected to start against Germany in Ireland's pivotal qualifier due to an injury to Séamus Coleman. Christie excelled in Ireland's famous victory against the World Champions. Ireland went on to qualify for UEFA Euro 2016.