Tesserae
These tokens known as tesserae, meaning "tile". They were evidence of your entitlements but also of your entanglements under Roman authority of the Roman world.
As a means of identification the original parties exchanged or displayed these tokens or tesserae hospitālēs.
In the Obligations of Hospitium there are obligations imposed by a covenant were of the most sacred character, and any failure to regard its provisions was considered sacrilege, bringing upon the offender, the anger of Iuppiter Hospitālis..
These ties were hereditary, descending from father to son, so that persons might be hospitēs who had never so much as seen each other, whose immediate ancestors even might have had no personal intercourse. As a means of identification the original parties exchanged tokens tesserae hospitālēs.[1]
When a stranger claimed hospitium his tessera had to be produced and submitted for examination. If it was found to be genuine, he was entitled to all the privileges that the best-known guest-friend could expect.
This same systems was use to provide government welfare. It is clear that these are almost precisely the duties an practices devolving upon members of our own great benevolent societies at the present time when appealed to by a citizen in distress.[2]
A tessera was the ancient Roman equivalent of a theater ticket. Stamped into a clay shard was an entrance aisle and row number for spectators attending an event at an amphitheater or arena. Above the doors of the Colosseum in Rome are numbers corresponding to those stamped into a spectator's tessera.
Tesserae frumentariae and nummariae were tokens given at certain times by the Roman magistrates to citizens, in exchange for which they received a fixed amount of wheat or money.[1] Smith, Sir William (1859), A dictionary of Greek and Roman antiquities (2 ed.), Little, Brown, and Co., p. 550 [1]
TES′SERA, dim. TESSE′RULA and TESSEL′LA (κύβος), a square or cube; a die; a token. "a small tablet (as of wood, bone, or ivory) used by the ancient Romans as a ticket, tally, voucher, or means of identification[2] "
"The Roman Empire used tiles called tesserae to identify slaves, soldiers, and citizens over 2,000 years ago."[3]
The tessera hospitalis was the token of mutual hospitality, and is spoken of under Hospitium, p619A. This token was probably in many cases of earthenware, having the head of Jupiter Hospitalis stamped upon it (Plaut. Poen. V.1.25; 2.87‑99).
Tessera frumentariae and nummariae were tokens given at certain times by the Roman magistrates to the poor, in exchange for which they received a fixed amount of cornº or money (Sueton. Aug. 40, 42, Nero, 11).
Frumentariae Leges. Similar tokens were used on various occasions, as they arose in the course of events. For example, when the Romans sent to give the Carthaginians their choice of peace or war, they sent two tesserae, one marked with a spear, the other with a Caduceus, requesting them to take either the one or the other (Gellius, X.27).From the application of this term to tokens of various kinds, it was transferred to the word used as a token among soldiers. This was the tessera militaris, the συνθημα of the Greeks. Before joining battle it was given out and passed through the ranks as a method by which the soldiers might be able to distinguish friends from foes. Thus at the battle of Cunaxa the word was "Zeus the Saviour and Victory," and on a subsequent engagement by the same troops "Zeus the Saviour, Heracles the Leader" (Xen. Anab. I.8 §16, VI.3 §25).
The soldiers of Xenophon used a verbal sign for the same purpose when they were encamped by night (VII.3 §34). Aeneas Tacticus (c24) gives various directions necessary to be observed respecting the word. Respecting the tessera or watchword in the Roman camp, see Castra, p251A .