Who was responsible for the construction of St. Basil's Cathedral in Moscow, and why?

St. Basil's Cathedral, originally called the Trinity Church, was commissioned by Ivan IV, Ivan the Terrible, to commemorate the defeat of the Mongols and capture of the Kazan, and the Khanate capital, Astrakhan in 1554. Today, it is officially known as Cathedral of the Intercession of the Most Holy Theotokos on the Moat.

The Cathedral was built on the edge of what is known today as Red Square. It was constructed between 1555 and 1561, and is one of the greatest architectural achievements to this day.

History and legend have it that Ivan IV, also known as Ivan the Terrible, had the architect blinded so he could not produce another building of this beauty or magnitude.