The Lego Castle theme is a segment of the broader Lego product line that encapsulates a medieval world concept, prominently featuring knights and castles. Launched initially in Europe in 1979 and later introduced to North America in 1981, the theme enjoyed continuous support until 1999. It was one of the original three Legoland themes along with Town and Space, with each of the three themes representing the 'Past' (Castle), 'Present' (Town) and 'Future' (Space).
Following this period, the "Lego Castle" name was revived for two separate series; the first spanning from 2007 to 2009, and a second series in 2013. While distinct, the Lego Castle theme shares thematic elements with other medieval-inspired Lego series, such as Knights Kingdom, Knights Kingdom II, and Kingdoms. The early iterations of Lego Castle sets were distributed under the "Legoland" brand until 1991, after which Lego transitioned the branding to the "Lego System" in 1992, marking a shift in the product line's presentation.
History
"Classic" Castle (1978–1983)
The Castle period from 1978 to 1983 predates themes or factions, and is often known as "Classic" Castle. 375 Castle (often called the Yellow Castle) is the most well-known set from this time.