Simplify the following text for a Grade 5 native English-speaking person.
Original: The story would not be finished until 12 years later , in 1949 , and would not be fully published until 1955 , when Tolkien was 63 years old .
Simplified: Tolkien wrote the story between 1937 and 1949 . It was originally published in three parts in the years 1954 and 1955 .