The Crimean war started when Russia invaded Turkish territories (current-day Romania). Britain, France, and the Ottoman Turks were allies against the invading Russians. The war began well, with the allies winning a few battles and gaining confidence. But once winter came, things degraded fast. The combination of the weather and the Russian intervention, the troops were cut off from supplies of food, fresh water, and medical supplies. Many soldiers were carted to nearby hospitals that were under-equipped and overwhelmed, only to die not long after arrival. Although this issue was not an uncommon one, the fact that there was a war correspondent back in Britain, the mistreatment of the troops reached the public. This led to a reform of the army staff and subsequently the roads, and overall sanitary conditions. This reform even led to what would be the standards for modern professional nursing. 

By spring of 1855, the British troops were much better taken care of. By the next winter, it was the French, not the British, that took the blow. Peace came after the loss of Stevanstopol and Kinberg, as the former had shaken the Russians. After the Austrians threatened to join the allies, the Russians signed the Treaty of Paris in March of 1856.