A first motte-and-bailey castle was besieged by Louis IV of France in 951. The Counts of Brienne are mentioned from 950 until 1356. A castle chapel, dedicated to the Holy Cross, is mentioned in 1166.
Abbot Étienne Charles de Loménie de Brienne became bishop, then archbishop, cardinal, and in 1787, a minister of state under King Louis XVI. His brother, Louis Marie Athanase de Loménie de Brienne, served as Secretary of War in 1787 and 1788 under the same king. This position prompted them to renovate their Brienne estate.
Both commissioned the reconstruction of the Château de Brienne, which began in 1770 and was completed in 1778, with the landscaping continuing for several years to create the exceptional view still admired today.
At the end of January and early February 1814, the area around Brienne was the scene of the Battle of La Rothière, during which Napoleon I directed operations from the Château de Brienne, where he spent two nights. According to Cassaigne, Napoleon nearly surprised the Prussian general Blücher at the castle through underground tunnels. In the ensuing assault, all the windows of the building were shattered.
After being sold and left uninhabited, the castle endured occupation during World War II, followed by abandonment until the early 1950s. The Brienne estate was converted in 1959 into a psychiatric hospital, now known as the Aube Public Mental Health Facility (EPSMA).
The site is not accessible to the visit excepting during the summer visits that could be origanized.
The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.