The battle took place at Podul Înalt ("the High Bridge"), near the town of Vaslui, in Moldavia (now part of eastern Romania).

The conflict between Stephen and Ottoman Sultan Mehmed II worsened when both laid their claims to the historical region of Southern Bessarabia, now known under the name of Budjak.

[14] Under Alexandru cel Bun, it had become an integral part of Moldavia and was successfully defended in 1420 against the first Ottoman attempt to capture castle Chilia.

This is confirmed by a German chronicle which explains that Mehmet wanted to turn Moldavia into "some kind of fortress", and from there, to launch attacks against Poland and Hungary.

[18] In 1448, Petru II of Moldavia awarded Chilia to John Hunyadi, the governor of Transylvania,[12] effectively ceding control of the strategic area on the Danube, with access to the Black Sea, to Hungary.

[20] Even though Hungary had made peace with the Turks in 1451, Hunyadi wanted to transform Wallachia and Moldavia into a barrier that would protect the kingdom from Ottoman expansion.

In April 1457, Vlad Țepeș supported Stephen with 6,000 horsemen, which the latter used to invade Moldavia and occupy the Moldavian throne,[24] ending the civil war as Aron fled to Poland.

[30] Mehmed was furious about the news and claimed Chilia for being a part of Wallachia – which now was a vassal to the Porte – and demanded Stephen to give it over to him.

[30] The Moldavian prince, realising that a future war with Mehmed could not be avoided, tried to gain time by increasing his tribute to the Porte by 50 percent (to 3,000 ducats); and also sent an envoy to Constantinople with gifts for the sultan.

The invasion ended in a disaster for the Hungarians as they suffered a bitter defeat at the Battle of Baia, where Corvinus was thrice wounded by arrows and had to be "carried from the battlefield on a stretcher, to avoid him falling into the hands of the enemy".

[34] In 1473, Stephen stopped paying the annual tribute to the Porte[35] and as a reaction to this, an Italian letter, dated from 1473 to Bartolomeo Scala, secretary of the Republic of Florence, reveals that Mehmed had left Constantinople on 13 April and was planning to invade Moldavia from land and sea.

[37] A series of "absurd"[37] clashes followed, starting with another confrontation between Stephen and Radu on 18–20 November, at Râmnicu Sărat, where the latter suffered his second defeat at the hands of the Moldavian "warlike" prince.

[37] In the spring of 1474, Laiotă took the Wallachian throne for the second time; and in June, he made the decision to betray his protégé by submitting to Mehmet.

[37] Stephen then invested his support into a new candidate, named Ţepeluş (little spear), but his reign was even shorter, as it only lasted a few weeks after being defeated by Laiotă in battle on 5 October.

For these already exhausted Ottoman troops, who had besieged the city from 17 May to 15 August,[31] the transit from Shkodër to Moldavia was a month's journey through bad weather and difficult terrain.

[40] According to Długosz, Suleiman was also ordered that after inflicting defeat on Stephen, he was to advance towards Poland, set camp for the winter, then invade Hungary in spring, and unite his forces with the army of the Sultan.

[42] In September 1474, the Ottoman army gathered in Sofia, and from there, Suleiman marched towards Moldavia by crossing the frozen Danube on foot.

His army rested in Wallachia for two weeks, and was later met by a Wallachian contingent of 17,000 under Basarab Laiotă, who had changed sides to join the Ottomans.

The winter made it difficult to set camp, which forced the Ottomans to move quickly and head for the Moldavian capital, Suceava.

To reach Vaslui, where the Moldavian army had its main camp, they needed to cross Podul Înalt over the Bârlad River.

[48] Instead, the centre of the valley held the Székely forces and the Moldavian professional army, which were ordered to make a slow retreat when they encountered the enemy.

[citation needed] Suleiman tried to reinforce his offensive, not knowing what had happened in the valley, but then Stephen, with the full support of his boyars, ordered a major attack.

[44] Only one was spared – the only son of the Ottoman general Isaac Bey, of the Gazi Evrenos family, whose father had fought with Mircea the Elder.

[44] After the battle, Stephen sent "four of the captured Turkish commanders, together with thirty-six of their standards and much splendid booty, to King Casimir in Poland", and implored him to provide troops and money to support the Moldavians in the struggle against the Ottomans.

[55] In response, "the arrogant Matthias writes to the Pope, the Emperor and other kings and princes, telling them that he has defeated a large Turkish army with his own forces under the Voivode of Wallachia".

[12] In the following year, Mehmed invaded the country with an army of 150,000, which was joined by 10,000 Wallachians under Laiotă and 30,000 Tatars under Meñli I Giray.

However, the Ottomans were unsuccessful in their siege of the Suceava citadel and the Neamţ fortress, while Laiotă was forced to retreat back to Wallachia when Vlad and Stefan Báthory, Voivode of Transylvania, gave chase with an army of 30,000.

In 1484, the Ottomans under Bayezid II managed to conquer Chilia and Cetatea Albă and incorporate it into their empire under the name of Budjak, leaving Moldavia a landlocked principality for many years to come.