Simplify the following text for a Grade 7 native English-speaking person.
Original: The city was burned down by the Tatars in 1513 , by the Ottomans in 1538 , by the Imperial Russian troops in 1686 .
Simplified: The Tatars burned the city down in 1513 . The Ottoman Empire also burned the city down in 1538 and people from the Imperial Russian army did so again in 1686 .