When was William Shakespeares last play?

Unfortunately we cannot really be certain which of his plays was the last one he wrote, or which was the last one to be performed. We can say for sure that based on the information we have, The Two Noble Kinsmen was the last to be published, in 1634, eleven years after the others. This might have been the last play which Shakespeare wrote unless it was the now lost Cardenio. Both were, scholars think (well Kinsmen says so on the title page) collaborations with Fletcher, and written no later than 1613. The Tempest (written probably around 1611 or so, due to the topical subject matter) is thought to be the last play he wrote without help from anyone else.