The name Red Square has nothing to do with communism, but derives from the word "krasnyi", which once meant "beautiful".
Built directly east of the Kremlin, Moscow's historic fortress and the center of the Russian government, Red Square is home to some of the country's most distinctive and important landmarks. Its origins date to the late 15th century, when the Muscovite prince Ivan III (Ivan the Great) expanded the Kremlin to reflect Moscow's growing power and influence.
Contrary to popular misconception, Red Square's name is completely unrelated to the crimson color of its numerous buildings as well as to the Communist Party's association with the color red. In its earliest incarnation, Red Square was known as Trinity Square, in honor of Trinity Cathedral, which stood on its southern end during the rule of Ivan III. From the 17th century onward, however, Russians began calling the square by its current name, “Krasnaya Ploschad.” The name is derived from the word krasnyi, which meant beautiful in Old Russian and only later came to mean red.