The Templar house of La Boissière was a Templar establishment that subsequently passed to the Order of the Hospital. From 1181 onwards, there is evidence of successive donations of property in Châteaudun to the Templars. In 1183, Count Theobald V of Blois (1130–1191) confirmed a donation made by Gaudefroy de l’Isle, followed by many others. In the mid-13th century, there is evidence of a dispute between the counts of Blois and the Order of the Temple.
Although there are references to a “commandery of La Boissière”, there is no evidence that the establishment was organised as such or, perhaps, that its existence was short-lived. At that time, the Order of the Hospital also held possessions in the town. In 1312, following the suppression of the Templars, La Boissière passed to the Hospitallers, who took charge of the establishment built by the Templars to provide for pilgrims, although the house remained essentially agricultural in character. It was a dependency of the commandery of Arville (Loir-et-Cher), which was united with that of Sours (Eure-et-Loir). The chapel of Notre-Dame, documented since 1221, in the time of the Templars, survives.
- BORDAS, Jean Baptiste (1884). Histoire sommaire du Dunois, de ses comtes et de sa capitale. Châteaudun: Société dunoise
- FOLLIOT, Pierre-Marie (1983). Les templiers dans la baillie de Chartres. La juridiction de Sours et d’Arville. Bulletin de la Société Archéologique d’Eure-et-Loir, núm. 96. Chartres
- MANNIER, Eugène (1872). Les commanderies de Gran-prieuré de France d'après les documents inédits conservés aux Archives nationales à Paris. París: Aubry
- MÉTAIS, Charles (1902). Les Templiers en Eure-et-Loir: Histoire et Cartulaire. Chartres: Archives du diocèse de Chartres, núm.VII
The chapel of La Boissière is located north of the town of Châteaudun