Iran, historically known as Persia, is a country in Western Asia with a civilization that dates back to one of the world's oldest continuous cultures. Its history stretches over several millennia, marked by the rise and fall of mighty empires such as the Achaemenid, Parthian, and Sassanian dynasties. As the heartland of the Persian Empire, Iran was renowned for its advancements in art, science, and architecture, as well as its elaborate administrative systems. The advent of Islam in the 7th century dramatically transformed the country’s cultural and religious landscape, with Iran later becoming a stronghold of Shia Islam. Throughout the centuries, Iran has played a pivotal role in regional and global politics, enduring invasions by the Greeks, Arabs, Mongols, and others, while also contributing richly to literature, philosophy, and the sciences. In the 20th century, Iran underwent significant political upheavals, culminating in the 1979 Islamic Revolution, which established the present-day Islamic Republic. Today, Iran maintains a distinct identity shaped by its ancient heritage and its complex modern history.