Diso was certainly founded before 1000 AD, as the inscription on the Mother Church confirms. The inscription underlines the fact that the building has been built on the remains of an earlier church, erected in 1003. But the small town dates back to a more ancient age, and several archaeological finds prove the presence of ancient populations such as the Messapians.
Since 1000 and for many other centuries, the history of Diso has been linked to that of theneighbouring Castro. From 1085, when Castro became a County, to the years of the Turkish raids (1537), Diso was a hamlet of Castro. Then, from 1806 to 1977, Diso acted as the main municipality of the area, ruling on the weaker municipality of Castro. Later, Castro managed to obtain its autonomy and is now an independent municipality.
After Castro was destroyed by the Saracen invasions, in 1600 Diso, became the most important city in the area, thanks to its great number of inhabitants and its strategic geographical position.For the whole 17th century, Diso experienced a building boom and a huge population increase. Most of the population worked as farmers, but there were also some notaries and doctors too. At that time, in the town there was a hospital.
At the beginning of the 18th century, Diso was hit by a severe economic crisis caused by both the Austrian reign and poor agricultural production. The latter lasted for a few years and led to a halt in all of the town activities, which resulted in massive migration flows towards richer areas.
However, in 1715, the few people who did not leave the town bought the two wooden statues of St Philip and St James, which are still today worshipped. In 1758 a new church dedicated to both saints was built. This was the most important period for the local monastery of the Capuchin Friars. And this was also the beginning of the rebirth of Diso.
The beginning of the 19th century marked the start of a new era for Diso. Thanks to the Napoleonic laws introduced in 1806, the town became the main municipality of the area, ruling over Marittima and Castro.
For more than a century, the three towns have been linked one to the others, with Diso always acting as the major centre. Later, however, the two smaller towns began to grow more and more, to the point that they became bigger than Diso. Thus, Diso has had to give Marittima and Castro a certain autonomy and in the townsnew facilities were built, such as schools, registry offices and chemist’s shops.
Over the years, the three towns have been involved in several disputes, often resulting in a series of compromises. Then, in 1977, Castro obtained its autonomy and became and independent municipality.
From that year on, Diso has only ruled over Marittima.