10 May – 20 August 1941: 1st Armored Division

10 October 1941 – 10 January 1942: 1st Armored Division

? ? 1941: Iron Cross 2nd class

1 August – 24 November 1942: 15th Infantry Division

? December 1942: promoted to maj. gen. (posthumously)

2 February 1943: Mihai Viteazul Order 3rd class (posthumously)

Ioan Alecu Sion was born on 28 September 1890 in Pitesti. He went to the Military High School in Iasi and then to the Artillery Engineers and Navy Officers School in Bucharest. In July 1911, the fresh 2nd lt. Sion was assigned to the 12th Artillery Regiment in Bacau. After two years he was detached to the Superior Artillery and Engineers School for the period between 15 October 1913 and 1 November 1914, finishing the 16th out of 41 students. He was promoted to the rank of 1st lt. and sent to the 2nd Artillery Regiment in Bucharest, where he received the command of the 2nd Battery/1st Battalion. With this unit he took part in the 1916 campaign, distinguishing himself in the fighting at Persani and Porumbacu. He was awarded the Coroana Romaniei Order Knight class. At the beginning of 1917 there was a wave of promotions in the Romanian Army and Ioan Sion became captain. He participated in the summer campaign of 1917 with the same unit and in October 1918 he was moved back to the 12th Artillery Regiment, commanding the 4th Battery. He was quickly noticed for his organizational skills and from November 1919 he was named chief of the Mobilization/Organization Bureau of the 8th Infantry Division, to which his regiment belonged to.

On 1 January 1921, Ioan Sion was promoted to the rank of major and in November of the same year he began the courses at the Military Academy. He graduated on 31 October 1923 and had to complete a stage at the 91st Infantry Regiment from Alba Iulia and then at the Romanian General Staff. From 1 May 1925 he became chief of the Mobilization/Organization Bureau of the 2nd Corps. After four years, in April 1929, he received the command of the 1st Horse Artillery Battalion and in October he was promoted to the rank of lt. colonel. He returned to an administrative job in April 1931 as chief of the General Secretary Service of the Ministry of War. In October 1933 he was moved to the Intelligence Bureau and in November 1934 he became secretary of the Superior National Defense Council. After two years, Ioan Sion was promoted colonel and received the command of the 1st AA Artillery Regiment. From November 1937 he was named chief of staff of the General Inspectorate of the Artillery. On 1 November 1939 he took overt he 2nd Artillery Brigade of the 2nd Infantry Division, distinguishing himself for the way he prepared it for war.

After general Antonescu came to power, col. Ioan Sion was named director of the Materials Department of the Undersecretary of State for Supplies. On 10 May 1941, he became brig. general and received the command of the newly created 1st Armored Division. The nominal commander was brig. gen. Nicolae Stoenenescu, who was in that period also the Finances Minister. Ioan Sion was the deputy commander, but in the absence of Stoenescu he assumed actual command. It was the first unit of its kind inj the Romanian Army, organized according to Wehrmacht doctrine and with the help of German instructors. Lacking many of the necessary materials, he had to work hard to prepare his division for combat. Unfortunately, the existing conditions didn't allow a complete training of the personnel and the acquisition of all necessary equipment.

The 1st Armored Division was initially to the German 11th Corps from the 11th Army. It started to cross the Prut River during the night of 2/3 July 1941 with its forward elements. The first combat actions took place on 4 July, when the Romanian tanks saved the 203rd Infantry Regiment of the German 76th Infantry Division from a difficult situation at Bratuseni. After this, the division of general Sion advanced up to the Dnister River, in the Moghilev area, until 7 July. There it waited to exploit the "Lindemann" Detachment's attempt to create a bridgehead over the river, but because this action failed, it was sent to the Soroca area with the mission to clear the Western bank of the Dnister of Soviet troops. On 11 July, brig. gen. Sion received the order to take his unit to Balti and from there he was sent down to Chisinau, where he would be subordinated to the German 54th Corps. Until 15 July, the 1st Armored Division crossed Bessarabia from North to South and was positioned thus that it could strike to both Chisinau and Orhei, according to necessity. The higher echelon decided that it should head towards the Bessarabian capital. Its appearance in this area constituted a big surprise for the Soviets and it contributed decisively to the occupation of Chisinau on 16 July. The division continued the pursuit of the 95th Rifle Division towards Tighina, but the heavy rains prevented its actions after 17 July. Following this date, general Sion and his troops were put in the reserve of the 4th Army and left to recuperate and repair their damaged equipment.

On 5 August 1941, the 1st Armored Division was subordinated to the Romanian 5th Corps and during the night it crossed the Dnister River. By 14 August it was then the spearhead of the 4th Army's attempt to encircle Odessa. On that day it was East of the city, only 10 km from the shore of the Black Sea. Then came the disaster at Karpova on 18 August, when the 1st Tank Regiment was detached to the 11th Infantry Division and 32 of its tanks were knocked out, due to the lack of cooperation with the 3rd Dorobanti Regiment. Thus, because the 1st Armored Division was left with only 21 operational tanks after that day, it was decided to form a Motorized Detachment and the rest of the division be sent for reorganization and repairs West of the Dnister.

Brig. gen. Ioan Sion was replaced by brig. gen. Carol Schmidt following marshal Antonescu's decision. He was unsatisfied by the division's performance in front of Odessa. The large number of tanks and vehicles damaged or destroyed couldn't have been the sole responsibility of Ioan Sion. His division traveled over 3,000 km since 16 June, when it left Targoviste, on very difficult roads. It was stripped of some of its vehicles and used to support units that were not trained to fight in cooperation with the tanks. Finally, as most of the Romanian divisions, it lacked all the necessary equipment. However, general Sion was an artillerist and didn't have the required experience to lead a mechanized unit. Practically, before the beginning of operations, he only had the opportunity to conduct several applications on the map. It seems that the Germans appreciated his exploits and awarded him the Iron Cross 2nd class at the end of 1941. On 10 October Ioan Sion returned to the command of the 1st Armored Division until 10 January 1942, when he was replaced by maj. gen. Radu Gherghe and he became deputy commander.

On 1 August 1942 he received a new command: the 15th Infantry Division. With this unit he went to the front, near Stalingrad, being subordinated to the 3rd Army of gen. Petre Dumitrescu. In November 1942, the division of general Sion was in the army's reserve, prepared to intervene on the Kletskaya – Ievstratovsky direction. On 19 November, when the Soviet counteroffensive north of Stalingrad, the 15th Division received the mission to block the Gromky – Ivanovsky road, but was attacked from Gromky by Soviet armored forces of the 4th Tank Corps. Finding it impossible to resist the onslaught, the only viable solution was to retreat to the West, where the 5th and 6th Infantry Divisions had resisted the initial attacks. By nightfall, these three divisions were almost encircled, forming the "Gen. Lascar" Group, which continued to hold out until 22 November. Because the Romanian troops were exhausted, lacked munitions and food, it was decided to try to brake out of the encirclement. Brig. gen. Ioan Sion was named commander of the attack column, while maj. gen. Mihail Lascar stayed behind to cover the retreat. The 30,000 men, spread along 30 km, started to march at 2100 hours. Taking advantage of the darkness, the column manager to sneak through the Soviet lines, arriving in Tsaritsa Valley, where it was attacked by tanks and completely disorganized. From the following slaughter, general Sion managed to escape with 3,626 men, 1,045 horses, 18 cars and two artillery pieces and arrived at Bol. Donchinskaya in the morning of 23 November, meeting up with the remains of the German 22nd Panzer Division.

Immediately the soldiers belonging to many different units were organized in a defensive formation, which could at least put up a minimal resistance. The main support were the few tanks of the German 22nd Panzer Division. However, these retreated during the night to a position 3 km from the village, which was under artillery bombardment. On 24 November, at 0300 hours, two Soviet tanks entered the village firing. Brig. gen. Sion and maj. Busuioceanu were permanently on the move, cheering up the men, handing out grenades, passing just 20 m from the tanks at one moment. Three times he asked for assistance from the 22nd Panzer Division, but he didn't receive anything. At 0700 hours more tanks started to appear near the village. He tried to launch a counterattack, but no one followed him. At 1000 hours the 303rd Tank Battalion/8th Guards Separate Tank Brigade attacked in force. The munitions were almost over and there were no AT guns available. The men panicked and started to run in disorder, through the Soviet artillery and machine-gun fire. He tried in vain to stop them. There was another massacre. Brig. gen. Ioan Sion remained behind in the village with maj. Busuioceanu, cpt. Severin, 2nd lt. Galben and his driver sold. Dascalescu. They decided to retreat to the positions of the 22nd Panzer Division, by marching through a small valley. The road was blocked by two infantry platoons supported by a heavy tank. They tried to escape by changing direction, but general Sion was hit and fell down.

He was the only Romanian division commander killed in action during WWII. His fate is characteristic for the drama endured by the Romanian soldiers at the Don's Bend in November 1942. For his deeds he was promoted posthumously and received the highest Romanian award for officers: the Mihai Viteazul Order 3rd class.