The first person to propose a heliocentric model (Earth revolving around the Sun) was Aristarchus of Samos, a Greek astronomer who lived in the 3rd century BC.

While his theory wasn't widely accepted at the time, he was the first to put forth the idea based on his observations and calculations.

It's important to note that his theory was largely overshadowed by the geocentric model of Ptolemy, which was the dominant model for almost 1500 years. It wasn't until the work of Copernicus in the 16th century that the heliocentric model gained wider acceptance.