Start Your Search In Ireland And The Uk
Both Ireland and the UK take historic preservation seriously, and one of the ways they've been able to fund restorations and upkeep is to rent out heritage homes to the public. In the UK, the organization that does this is called the British Landmark Trust (www.landmarktrust.org.uk); in Ireland, it's the Irish Landmark Trust (www.irishlandmark.com).
Both administer and own houses of historical or architectural import. In England, for example, the rentable properties include Clytha Castle, a "folly" built in 1790 to resemble a medieval castle; Wortham Manor, a Tudor manse that looks like something the worthy suitor in a Jane Austen novel would own; and a thatched, stone cottage in Devon with a perfectly preserved, 16th century interior. The offerings in Ireland are as tempting, from actual lighthouses (several of them) to quintessential Irish cottages (with turf fireplaces) to a medieval tower-house surrounded by a working farm.
While their offerings can be pricey, last-minute deals lower costs considerably (I've seen four-night midweek breaks drop to just £70 a night, for a home that can sleep up to four people). Certain of the larger properties also work out to be quite economical on a per person basis... if you can fill all the rooms.