The cast had many adventures, meeting numerous people as a result. Though the most important person that they met happened to be a young sailor. In 1929, Castor and Harold were on an adventure as Castor was attempting to concoct another get rich quick scheme (seemingly because investing in the stock market was going to soon be a bad idea) and had to recruit a sailor to travel by boat to their next destination.
With those forearms, I doubt anyone knows exactly what you are, Popeye.
The rest is sort of history. The strip would eventually be renamed "Thimble Theater starring Popeye" and then simply "Popeye." The strip is still carried and drawn today, over 90 years after its initial appearance and Popeye continues to be a very popular character.