Justinian I was a Byzantine Emperor who like previous eastern emperors before him had to deal with Persian invasions. I about 524 the Persians again making in roads into Mesopotamia. Justinian was at this time waning to expand his empire to the west but was forced to send troops to force the Persians back. Belisarius was to lead the army and his being Justinian's best general you can be fairly sure his best troops were also sent. This lead to a fairly long campaign and in 530 he won a great victory at the battle of Dara defeating a combined army of Persians and Arabs of about 40,000 troops. This he did by using the infantry in defencive positions whilst aggressive use of his cavalry.
Around this time the Persians also suffered a second defeat in the Caucasus by Sittas at Satala. This left the Byzantines in a strong position at the start of the campaigning season of 531 after failed negotiations to end the war but this was turned on it's head when Belisarius was defeated by superior numbers at Callinicum though he was able to withdraw the remains of his campaign weary army to the city of Sura astride the River Euphrates. Here he withstood repeated attacks but was unable to take offencive actions himself.
Things improved wen King Kavadh I died in 531 and his son concluded the eternal peace which lasted all of eight years. The peace required both sides to give captured territories back though Persia was to keep Iberia with the displaced people given the choice of returning home or staying within Roman controlled provinces. Justinian was also to pay a tribute of 110 Centenara (11,000 lb of gold).
OK not quite as obscure as many but have you seen J, it's not exactly packed with options LOL.
Wargaming the period is really quite easy as figures are readily available in most scales you would like. By this point the Persians had taken note of Roman methods of siege and both sides conducted successful and failed sieges and more battles than the two mentioned happened though not all were with full armies. The Persian aim all along was to gain tribute from the Romans and this could be worked into a campaign were with each success the Persians will gain x tribute at the end of the campaign and set levels equate to levels of victory. Besides what wargamer could resist playing for imaginary wealth? The main advantage for the Persians was that they were safe from invasion from their other boarders as the terrain made this almost impossible whilst the Byzantine were already involved in other wars and incursions. This was not the all conquering Roman armies of days gone past. The Persians made good use of bow armed light cavalry and heavily armoured lance cavalry which worked well against the Byzantine armies until they adopted some of the same troop types and started to get the edge on the Persians.
Also in the first few years both sides used smaller armies of vasel states to do the fighting. This only came to the end with the death of Kavadh when better troops and commanders were sent by Justinian forcing the Persians to do the same. Up to this point the Persians tended to do better in the battles. About this time the Iberian revolt (originally supported by the Byzantines) had been put down releasing more Persian troops.