After the decline of the Teutonic Order following its defeat in the Battle of Grunwald in 1410, and the defeat of the Livonian Order in the Battle of Swienta on 1 September 1435, the Livonian Confederation Agreement was signed on 4 December 1435. The Livonian Confederation ceased to exist during the Livonian War (1558–82). The wars had reduced the Estonian population from about 250–300,000 people before the Livonian War to 120–140,000 in the 1620s. The Grand Duchy of Moscow and Tsardom of Russia also attempted invasions in 1481 and 1558, both of which were unsuccessful .
What event preceded the decline of the Teutonic Order?
the Battle of Grunwald

During the 19th century, Britain and the Russian Empire vied to fill the power vacuums that had been left by the declining Ottoman Empire, Qajar dynasty and Qing Dynasty. This rivalry in Eurasia came to be known as the "Great Game". As far as Britain was concerned, defeats inflicted by Russia on Persia and Turkey demonstrated its imperial ambitions and capabilities and stoked fears in Britain of an overland invasion of India. In 1839, Britain moved to pre-empt this by invading Afghanistan, but the First Anglo-Afghan War was a disaster for Britain.
What was the British-Russian rivalry called?
the "Great Game"

There is a wide consensus that the racial categories that are common in everyday usage are socially constructed, and that racial groups cannot be biologically defined. Nonetheless, some scholars argue that racial categories obviously correlate with biological traits (e.g. phenotype) to some degree, and that certain genetic markers have varying frequencies among human populations, some of which correspond more or less to traditional racial groupings. For this reason, there is no current consensus about whether racial categories can be considered to have significance for understanding human genetic variation.
What do some people contend racial categories are obviously correlated with?
biological traits