Some eighty years ago, Prime Minister Winston Churchill of the UK declared about the Soviet Union: "It is a riddle wrapped up in a mystery inside an enigma". The same statement could be applied to China. Both countries, particularly Russia for the past 100 years, and China since 1949, have been little known, and less understood by outsiders, even scholars in their fields of Sinology and Russian affairs. Due to a lack of accessible sources, their foreign policies have been less understood, particularly their relations with each other. In this course we will examine the course of Russian and Chinese Relations from 1689 to the present, or some 330 years. It is a relationship full of ups and downs. The two countries have shared the longest border in the world. The two countries have gone from alliances to battles. Lastly, we shall examine the state of Russian and Chinese Relations today, a state Russian scholars call a "strategic partnership", or even an alliance. We shall look at major issues that have drawn the two states together, and those that continue to divide the two powers. By the end of the course, students should have a balanced picture from Russian, Chinese and Western scholars of the course and development of Sino-Russian (Soviet) relations since 1689. We will try to reduce here the "riddle wrapped up in a mystery inside an enigma".