Green has bought Castle Marcei, near Argentan in Normandy for just over 400,000 euros.
In an interview with Ouest France, he said: "I just wanted to buy a property in Normandy to live with my 30 horses.
"I've always been fascinated by the throughbred. Normandy is the epicentre of the horse world, this is where I decided to start a new life."
Green visited 30 properties before buying the 18th century castle and 27 acres of surrounding meadow and woods.
He added: "in each of my visits, it is as if the castle told me: 'buy me'.
"I hope to finish the work within three months and bring my horses."
Green was paid almost £1m in 13 months at Rangers, according to the club's accounts. The Yorkshireman received a salary of £333,077, a £360,000 bonus and benefits which amounted to £22,449. He also received a severance payment of £217,850.
Another former owner of Rangers, Craig Whyte, owns Castle Grant in Grantown-on-Spey.