Actually, Warsaw is older than it seems from the first sight. First settlements in the area date back to the 10th century and the first records back to the 11th century. The city itself was founded in the early 1300s.
The city of Warsaw itself was founded in the early 14th century when the dukes of Mazovia built a stronghold on the site where the Royal Castle now stands. About a century later Warsaw becomes the base for the dukes of Mazovia, and the city grows beyond the surrounding city walls. But in 1526 the whole Mazovian Duchy including Warsaw was incorporated into the Polish crown with a capital in Krakow. Warsaw remained a political backwater until Poland and Lithuanian unified in 1569. 27 years after the unification King Zygmunt III Waza moved the capital from Krakow to Warsaw. Warsaw was soon to suffer terribly from the Swedes. Between 1655 and 1658, Warsaw was thrice besieged and entirely plundered by the Swedish troops. But before the century ended the political situation had stabilized and Warsaw again became an important center of culture, education, and enlightenment. This period, led by King Stanislaw August Poniatowski, was later coined as Warsaw's second "golden era". It's really important to note that the first democratic constitution in Europe (second only to the United States) was declared in Warsaw on May 3, 1791.
During of three partitions of Poland held by Prussia, Austria and Russia in 1772, 1793, and 1795 Warsaw has went through the times of decline. Being first under the Prussian rule its role reduced to the ordinary provincial town but later after coming under the Russian rule city's reputation and significance was reestablished.
Then Poland regained its independence only after the end of World War I with Warsaw as a capital.
The Nazi troops invaded Poland on the 1st of September, 1939. Resistance lasted for 28 days but Warsaw fell despite the heroic efforts of its defenders. But resistance continued throughout the war, marked notably by two uprisings in 1943 and 1944. About 85% of the city was reduced to rubble during the last months of World War II. On the 17th of January, 1945 the Red Army invades Warsaw and liberates the city from the German rule.
Warsaw was rebuilt after World War II. The Royal Castle and the surrounding Old Town was reconstructed from pictures dated to the 17th and 18th centuries.
Nowadays the Polish capital is on the rise again. It moves forward while remaining its unique ambience and atmosphere.