The discovery by Father Agostino Grazzi of the tomb of a Picene warrior and significant artifacts (armors, fibulae, dagger blades, pottery) testifies to the presence of human settlement in this area as early as five hundred years before Christ. There is also evidence of continuous habitation during the Roman Empire and even in the first three centuries of Christianity, as evidenced by some Early Christian mosaics discovered by chance in 1956 during sewer system renovations within the walls of the castle.
In the 13th century, there was a settlement of monks, initially on a hill just a few dozen meters from the current castle, under the feudal jurisdiction of the Bishop of Jesi. On this hill stood a “villa” and the church of San Marcello al Poggio, still visible today, in Romanesque-Benedictine style, which housed a fresco depicting a crucifixion by the Fabriano school, now restored and displayed in the parish church. The Church of Santa Maria del Monte (a few kilometers from the castle) and the Gothic Crypt (at the foot of the parish house—outside the castle walls) date from the same period.
In 1261, the Castle of Poggio San Marcello is mentioned as an already established and fortified urban center.
The Castle of Poggio San Marcello came under the control of the powerful city of Jesi in 1301, as confirmed by an ancient parchment from 1530. The 1600s and 1700s saw a vibrant life in the area, as evidenced by some beautiful buildings within the walls, including the Town Hall, designed by Andrea Vici of Rocca Contrada (now Arcevia).
From 1929 to 1946, the municipality of Poggio San Marcello was annexed to the nearby municipality of Castelplanio, becoming a fraction of it. This annexation caused great discontent among the citizens and created fierce rivalry with the neighbors of Castelplanio, leading to a series of anecdotes, including that of the new bell, a source of pride for the people of Poggio. They wanted to have it passed through the streets of Castelplanio as a symbol of pride. Since this wasn’t technically possible, only the clapper was passed through, symbolizing that “if it’s as much as it is, the clapper is big, imagine the bell!”