Opus Postumum was the last work by the German philosopher Immanuel Kant, who died in 1804.

One of the problems experienced in handling the manuscript is that the individual sheets of paper had not been bound, and following Kant's death curious people visiting his house messed up their order.

[1] Johann Friedrich Schultz, a close friend and trusted expositor of Kant was presented with manuscript by Kant's executor, Ehregott Andreas Wasianski [de].

Schultz then passed them onto Carl Christoph Schoen, who had married Kant's niece.

The manuscript remained lost amongst his papers for fifty years only to be discovered by his daughter after his death.