Budapest's origins date back to a Roman times, although the ancestors of today's Hungarians are more recent - around 900AD. The cities Buda and Pest were repeatedly destroyed and conquered, but in the 17th and 18th centuries managed to stabilise and rapidly expand. The cities and various districts were fused into one city in the mid-1800s, and Budapest continued to grow to a high point of around 2 million inhabitants in 1990. Since then, it has fallen back a little to around 1.7million, but remains the sixth largest city in Europe.