Robert Newton not only brought Long John Silver (and what we conceive to be pirate-speak) to life, but he even died playing Long John Silver. Now that is commitment to a role.
That isn’t literally true, but it’s close to the truth. Some four or five years after Treasure Island left the theaters, he filmed 26 episodes of a TV series called The Adventures of Long John Silver. If you are curious, many if not all of the episodes are on YouTube in their entirety, and they were filmed in color, even though few people owned color TVs at the time. If Wikipedia has the dates right, Newton was alive when the series first aired in the USA from September of 1955 through early 1956, but had passed away before the series made it to the UK the following year.