The Grass Crown () or Blockade Crown (corona obsidionalis) was the highest and rarest of all military decorations in the Roman Republic and early Roman Empire. It was presented only to a general, commander, or officer whose actions saved a legion or the entire army. One example of actions leading to awarding of a grass crown would be a general who broke the blockade around a beleaguered Roman army. The crown took the form of a chaplet made from plant materials taken from the battlefield, including grasses, flowers, and various cereals such as wheat; it was presented to the general by the army he had saved.
Pliny wrote about the grass crown at some length in his Natural History (Naturalis Historia):
Pliny also lists the persons who by their deeds won the grass crown: