The ori­gins of Tallinn date back to the 13th cen­tu­ry, when a cas­tle was built there by the cru­sad­ing knights of the Teu­ton­ic Order. It devel­oped as a major cen­tre of the Hanseat­ic League, and its wealth is demon­strat­ed by the opu­lence of the pub­lic build­ings (the church­es in par­tic­u­lar) and the domes­tic archi­tec­ture of the mer­chants‘ hous­es, which have sur­vived to a remark­able degree despite the rav­ages of fire and war in the inter­ven­ing cen­turies.