Schlieman, a 19th century German merchant, started his life poorly. At 11 he began to work 15 hours days as a grocer's clerk, and after two years n accident with a heavy load he carried forced him to look for another job, and he soon ended as a file clerk in an office in Amsterdam. He soon realized that if he wanted to get something from life, he had to improve himself. Working in the import-export business, he decided that if he learned a foreign language, he could probably get a better paying job.

Schliemann wrote an "authorized" autobiography in 1875 (in english), where he explains how he and why he learned all these languages, among other things.

You can get this book from Amazon.com for about 12$, which is the best price I found,   or if you live in Europe as I do, from Amazon.co.uk.