The former purely agricultural Slavic village shares an architectural connection with the town of Svitavy. Lačnov, whose territorial border divided Bohemia from Moravia, is documented as far back as the beginning of the 14th century.
In 1330 the lost Lačnov magistrate’s privilege, granted by Bishop Bruno, was restored. The name of the village is taken from the personal name Lačen, the Czech equivalent of the German name Lotschnau. From its founding the settlement was part of the Svitavy administrative circuit and had a common history with the town, first as an independent and later an integrated village. The dominant feature of the village was the Baroque Marian chapel with a tower built in the year 1749. The interior of the chapel was furnished and decorated with pictures from the years 1779-1840; the Stations of the Cross paintings were produced by Svitavy artist Johann Dittmann. The Virgin Mary Chapel was razed in 1971 and the construction material was used to build a grocery store. Standing in the middle of the village is the Baroque Holy Trinity statue by an unknown master from 1869 and a column with a statue of St. John Nepomuk can be found in the garden of House No. 31. Several Baroque crucifixes are located in the village and are the work of local artists, mainly from the 2nd half of the 19th century. A rough 17th century propitiatory cross, put up in memory of a murdered farmhand, is located at the crossroads at Kosíř. The boundary stone of the domain is located near the cross.