Built in the 18th century, the structure served as the ancestral seat of the Browne family, who later became the Marquesses of Sligo. The castle’s strategic location, overlooking Clew Bay with Croagh Patrick in the distance, made it both a defensive stronghold and a statement of power during a turbulent period in Irish history.

The castle underwent significant transformations over the centuries, most notably under the direction of architect James Wyatt in the 1770s. Wyatt’s neoclassical renovations transformed what was originally a more modest fortified house into an elegant Georgian mansion, complete with ornate plasterwork, a magnificent staircase, and rooms designed for entertaining the Anglo-Irish elite. The surrounding demesne was landscaped to include formal gardens, woodlands, and a lake; creating one of Ireland’s finest examples of an 18th-century designed landscape that still attracts thousands of visitors annually.

Today, Westport House and its demesne offer a unique window into Ireland’s complex past, where the grandeur of the Big House tradition meets the reality of post-independence Ireland. The estate has adapted to modern times by opening its doors to the public, hosting everything from historical tours to adventure activities. The castle’s dungeons, which once held prisoners during the 1798 Rebellion, now serve as a sobering reminder of Ireland’s struggle for independence, whilst the beautifully preserved state rooms showcase the artistic and architectural achievements of the Georgian era.