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From 1853 to 1856 , the peninsula was the site of the principal engagements of the Crimean War , a conflict fought between the Russian Empire and an alliance of France , Britain , the Ottoman Empire and Sardinia .
 Russian Empire, France, Britain, Ottoman Empire, Sardinia
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Russian Empire, France, Britain, Ottoman Empire, Sardinia