Original: Lothair received the central portion of the empire - what later became the Low Countries, Lorraine, Alsace, Burgundy, Provence, and the Kingdom of Italy (which covered only the northern half of the Italian Peninsula), collectively called the Middle Frankish Kingdom.
Simplified: Lothair got the central part of the empire - what later became the Low Countries, Lorraine, Alsace, Burgundy, Provence, and Italy.