The expletive, "Holy Toledo," refers to Toledo, Spain:
ancient (Latin) Toletum , or (Arabic) Tulaytulah city, capital of Toledo provincia, which is situated in the comunidad autónoma (“autonomous community”) of Castile-La Mancha, south-central Spain, on a rugged promontory washed on three sides by the Tagus River. It lies 42 miles (67 km) south-southwest of Madrid.
Of ancient origin, Toledo is mentioned by the Roman historian Livy as urbs parva, sed loco munita (“a small city, but fortified by location”). Conquered by the Roman general Marcus Fulvius Nobilior in 193 BC, it became an important Roman colony and the capital of Carpentia. The city was the residence of the Visigothic court in the 6th century and site of the famous councils, the third of which (589) was particularly important because of King Recared's conversion to Christianity. During the Moorish period (712–1085), it was the home of an important Mozarab community (Arabic-speaking Christians). Taken by King Alfonso VI in 1085, it became the most important political and social centre of Castile. It was the scene of a fusion of Christian, Arab, and Jewish culture, an example of which was the School of Translators (Escuela de Traductores) established by Alfonso X the Wise in the 13th century. The city's importance declined after Philip II made Madrid his capital (1560).