The Imperial Russian Army was the military force of the Russian Empire from the 18th century until the early 20th century. It played a crucial role in various conflicts, including the Napoleonic Wars and World War I. The army was known for its large size and diverse composition, consisting of soldiers from various ethnic groups within the empire. The army underwent significant reforms in the 19th century, particularly under leaders like Tsar Alexander II. These changes aimed to modernize the military and improve training and equipment. Despite its strengths, the Imperial Russian Army faced challenges, including logistical issues and outdated tactics, which contributed to its struggles in later conflicts.