Richard's shield was one of two markers left by the Knights of the First Crusade, describing the location of the Holy Grail. It was placed in the tomb of Sir Richard, one of the three knights in the mid-12th century. Richard had died on the trip home to France from the Grail's location. The inscription on the upper right section of the metal shield was an exact match to the Grail tablet, left in Turkey.
In 1938, the partially flooded Knight's tomb was discovered by Indiana Jones and Elsa Schneider in the catacombs of Venice, underneath the church, using research notes left by Henry Jones, Sr.. Indy opened the tomb to discover the shield, buried with the knight. He recognized that inscription on the shield matched the inscription on the grail tablet, and made a rubbing of the shield's text.
When a fire set by members of the Brotherhood of the Cruciform Sword reached the knight's tomb, Indy and Elsa dumped the shield and Richard's corpse out of the stone coffin, and flipped it over, providing a temporary shelter until they could find an escape. With a rubbing made, the shield had to be abandoned in the oily waters of the tomb when the petroleum was set alight.
The full inscription and translation on the shield read:
"...Knights of the First Crusade, while besieging the city of Alexandretta + Lord... God Almighty and Eternal... we owe love always and wheresoever... to give thanks to Thee through Jesus, Thou, O God... Through Christ Our Lord, Jesus Christ... Almighty God and... Eternal... loving who you gave to the Knights of the First Crusade... while besieging the city of Christ, Alexandretta, we owe + water... always and everywhere there... to give thanks through Jesus... Our Lord... who drinks the water... I shall give him, will have a spring inside him welling up eternal life... O Lord, King of our severe gods... blessed are they who dwell in thy temple, O Lord... they praise you for all time... You, God, are my refuge : Send forth Thy light and Thy truth + These shall be my guide : They shall lead me to Thy holy mountain in the place where you dwell : through the canyon of the crescent (waxing) moon: narrow enough for one man... to the temple of the sun, holy enough for all men... + where the Grail that holds the blood of Our Jesus Christ dwells forever... God, holy enough for all men..."―Indiana Jones's translation[src]
According to Jones, the inscription made several references to Christ's words to the Samartian woman at the well in the book of John, Ch. 4 and Psalm 42. He kept the rubbing in his journal as well as his translation.