Part of this fresco showed Augustine as a bishop. Another part showed him at his moment of great restlessness and conversion in the garden of Milan, with his mother Monica praying fervently not far away.
In 1366 the eremo was fortified in order to offer shelter in the event of war for the population of the village of Santa Colomba (10 km from Siena and 50 km from Florence).
The eremo received a visit from Pope Pius II (Pope 1458 to 1464) in 1460. Siena was the area of birth of Pius, and while Pope he spent some time there.
In the fifteenth century, another artist was commissioned to assist the eremo. He was Giovanni di Paolo (1399/1403 – 1482). For San Leonardo da Lago he painted his only fresco, the Crucifixion.
He also made the Antiphonal - illuminated choir book - made for the eremo of Order of Saint Augustine monks at the Eremo di Lecceto. It is now displayed at the Biblioteca Communale degli Intronati, Siena.
The eremo of San Leonardo da Lago had a community of the Tuscan hermit grouping formed by the Little Union of 1244 until the changing patterns in society and in the church - especially after they were swept into the Grand Union of 1256 - saw the focus of their ministry turn much more to the growing populations of the cities.
In the face of this reality, the eremo was suppressed in 1782 by the Grand Duke of Tuscany. He amalgamated it with the Eremo of Lecceto, which he also suppressed.
In 1808, the government of Napoleon evicted the Augustinian community from Lecceto.
Although the Order of Saint Augustine returned to Lecceto (after an Augustinian absence of 162 years, with Augustinian contemplative nuns as recently as 1972), San Leonardo da Lago is still government property and part of the national heritage of Italy.
Unfortunately the hermitage is closed to the public. The exterior of the church has an interesting façade, which can be viewed. It has a rose window over the main doorway.
Near the church are remains of the Augustinian monastery, which is now used as a residence for the caretaker of the property.