Thomas Ion Victor Ferguson known as Ion Ferguson Royal Army Medical Corps (1913 – 1990) was an Irish volunteer for the British army who escaped from Oflag IV-C, Colditz Castle, during the Second World War.

In 1939, at the outbreak of World War II, the family moved to Croft House in Church Street, Whitworth, Lancashire a small town north of Rochdale.

After the German invasion the squadron was forced to evacuate to Crete until 15 May 1941 and then back to Egypt with the three remaining airworthy Blenheim aircraft.

According to Punch magazine, "Dr. Ferguson is a typical Irish rebel who kicked against the authority of senior officers until becoming a POW, when he would not allow the Germans to ill-treat anyone without voluble protest.

His intransigence landed him in Colditz ..."[1] At Colditz Ferguson wanted to attract the attention of the German authorities; he wrote a letter to an Irish friend, the son of Éamon de Valera, the Irish Taoiseach.