Farmingdale sits near the eastern end of what was the Hempstead Plains, the vast, treeless prairie that covered central Nassau County. Englishman Thomas Powell purchased about 15 square miles, including the area that became Farmingdale, from the Marsapeque for 140 pounds in 1695. He and his children divided the land into lots and began more than a dozen decades of agriculture in the area.

Over time, a gristmill, a tavern and a few other businesses were established. The community that formed called itself Hardscrabble. Whose idea that was remains unknown. Real estate speculator Ambrose George opened a general store in Hardscrabble in 1841 and bought several acres of land. He changed the name of the hamlet to Farmingdale by 1845, subdivided his land and laid out streets. Within a few decades, industry began to locate in Farmingdale, including a lumberyard, a brickworks and at least six pickle factories. The bricks were used for buildings as near as Garden City and as far as Chicago.

The village was eventually incorporated in 1904. The farms provided an impetus for the state to establish the Agricultural and Technical College in 1914. Many of the remaining farms were bought out in the years after World War I, when aircraft companies - particularly Liberty - looked for manufacturing space. The industrialization resulted in the village's population doubling by the mid-1930s. The last open spaces were gobbled up by the post-World War II building boom.