Late March 633, Southern Mesopotamia
Bahman Jaduya was standing in front of a man, reading a letter addressed to the former.
"Submit to Islam and be safe. Or agree to the payment of the Jizya, and you and your people will be under our protection, else you will have only yourself to blame for the consequences, for I bring the men who desire death as ardently as you desire life, huh? What kind of nonsense is this?"
" I thought so too, general Jaduya. But I first thought I'll consult it with you. I received this letter this morning, apparently from Arab general Khalid ibn al-Walid. How do you think I should respond?"
"Hormozd, you are not supposed to respond to these kinds of letters. What he demands from you, from all of us, is unreasonable. I advise you to not respond."
"If you say so, general."
The man was Hormozd, a governor of Dast Meisan, or southern Mesopotamia, loyal to the Persian Shahanshah. He was one of the first reporting the eminent Arab invasion, and now the first to report its beginning. The proof was the letter he got, basically a declaration of war stating that if he wants to live, he should either convert to Islam or pay a special tax to be spared. If he refused both options, there was the third. Bloodshed.
"General, I shall begin assembling an army immediately to face the enemy."
"Great. I shall then make a report and send it to our Shahanshah, may he be immortal."
Hormozd nodded and the two men parted their ways, one going on about the official and formal inquiries, the other went off to war.
Hormozd managed to form an army by April, consisting of mainly heavy infantry and cavalry. He wasn't able to get some elephants into his army, which he considered to be an inconvenience. Persians have used elephants on many occasions in many different battles, with these strong animals always helping their army very heavily. He was also aware of the supply routes and low mobility of his army. This was the Persian strategy – the decisive battle doctrine. Before his departure, he met with 2 other men. Qubad and Anoshagan. These two men were the other commanders in his army. They discussed the plan of their journey.
"The letter from that Arab Khalid was sent to me from Yamama through Kazima. I'd guess they'll march through there – along the coast. Let us march towards Kazima, I think they're waiting for us there."
Other generals agreed rather quickly as there was not much to discuss. If the enemy marched through Hufeir rather than Kazima, they could always just change directions. They just had to defend the port of Ubalia, which was an important port for the Sassanian Empire – one of the main ones in the Persian Gulf.
Hormozd wanted to visit his wife, who was pregnant during that time before marching into battle, but duty called and they didn't have much time. He had to go.
He set off into the desert along the Persian gulf, moving his army slowly to not tire them off. The heavy armoured soldiers would tire themselves out very quickly if they didn't have regular pauses during the march. At least the cool wind from the Persian Gulf was keeping their spirit and temperature up. Hormozd's army numbered 20000 men, mainly Christian Arab auxiliaries and heavy cavalry. This composition was very common for the Sassanid army and Hormozd didn't see anything wrong with it.
In 14th April 633, Hormozd and his army arrived in Kazima, only to find no traces of Muslim army, only to hear scouts report that Arabs are advancing of Hufeir. Of they went through and continued, fall of Ubalia would be unpreventable. And he couldn't allow that. Hormozd immediately ordered a quick regrouping and march towards Hufeir. He completely forgot the heavy armour his soldiers wore and force marched them to Hufeir. But the Arabs weren't in Hufeir either.
Khalid was laughing as he heard the scouts reporting the Persian army's forced march in Hufeir, only to find they weren't there. Khalid was very well aware of the heavy armour and low mobility Persian army had, and chose to wear them out. He and his army went through the desert back to Kazima, where he waited for Persians, leaving the desert behind them so they could retreat easily.
When Hormozd and his army arrived at Kazima, they were tired. But they had to fight. They tied themselves together with chains – to prevent Arab cavalry to charge them and cause breakthroughs and to show the enemy their unity and their resolve to either win, or die.
"Persian soldiers! Our resolve and unity is unshakable as Zagros mountains, as holy as Yazd Fire-temple and as mighty as the Achaemenid Empire of old! Today, we shall prevail!"
"God's warriors! These fire-worshipping wretches dared to stand against our God, our Saviour! In his name, we shall cleanse these lands of the Persians, trembling around their fires and replace their fire with our all-mighty God! Allahu Akbar!"
The battle has begun.
The first lines of exhausted soldiers bound by chains were quickly charged by Arab light cavalry. The soldiers fought as they could, but the exhaustion was a strong disadvantage. When the infantry also clashed with Persians, the line began to fall. Persian cavalry was, although effective, quickly defeated due to its small number. Hormozd observed the battle from afar, looking with a sour expression. He didn't have a high chance and he knew it. In the corner of his eye, he saw a differently dressed figure, riding into the battle. Arab general, no doubt. Hormozd thought and ached for a while, before resolving himself. He charged into the battle.
After a few slashed faces and cut arms, he finally stood face to face with the man. Khalid ibn al-Walid was his name. General against a general, a duel to write the outcome of this battle. Khalid grinned and attacked Hormozd, swinging from below. His sabre clashed with Hormozd's and sound of clanking steel could be heard all around. Hormozd swung from the side, trying to feint it and changing directions. Khalid's quick reactions saved him as he dodged. Not completely though, having his side cut into. His face groaned in pain. Then he stabbed towards Hormozd, who dodged and tried to counterattack. Then he felt the painful, hot feeling in his stomach and saw Khalid's arm just below his chest. He knew what happened. His life flew through him and out of him, quickly disappearing. Khalid grinned again.
"Looks like Allah has not accepted you, infidel."
Hormozd, with the last bits of his strength, grinned, looked up at Khalid in the eyes and responded.
"It was me who didn't accept him, you scum."
Then, the last bit of life quickly disappeared from him, leaving a corpse of a former great man just another casualty on the battlefield. Khalid was so angered by his response he ordered Hormozd's body crucified. After Hormozd's death, the Persian army was ordered to retreat by the remaining commanders, but because lot of soldiers were bound by the chain, they weren't able to escape the onslaught at the hands of the Arabs. The Persians were defeated and Arabs marched on Hira.