Ottoman Russia

By revolutionizing and modernizing Russian arms, including the creation of Russia’s first naval force, Peter was able to pursue an aggressive and expansionist foreign policy that set the stage for the way the European map would be redrawn again and again over the coming centuries. Some of those forays were memorably countered by Western Europeans and the Holy League, but the Ottomans’ most frequent foe was the Russian Empire, which opposed them for both geopolitical and religious reasons.

In terms of geopolitics, perhaps the most seminal event of the Middle Ages was the successful Ottoman siege of Constantinople in 1453. The city had been an imperial capital as far back as the fourth century, when Constantine the Great shifted the power center of the Roman Empire there, effectively establishing two almost equally powerful halves of antiquity’s greatest empire.

In terms of geopolitics, perhaps the most seminal event of the Middle Ages was the successful Ottoman siege of Constantinople in 1453. The city had been an imperial capital as far back as the fourth century, when Constantine the Great shifted the power center of the Roman Empire there, effectively establishing two almost equally powerful halves of antiquity’s greatest empire. Constantinople would continue to serve as the capital of the Byzantine Empire even after the Western half of the Roman Empire collapsed in the late fifth century.