Battle of the Cosmin Forest The Battle of the Cosmin Forest ( 1497 ) ( ; ) was fought between the Moldavia n Prince , Ştefan cel Mare ( " Stephen the Great " ) , and King John I of Poland ( " John Albert " ) of the Kingdom of Poland . The battle took place in northern Moldavia , about 50 km north of the - then capital of Suceava ( ) , in the hills between Adâncata ( nowadys Hlyboka ) , situated in the valley of the Siret River , and Cernăuţi ( nowadays Chernivtsi ) , situated in the valley of the Prut River , and resulted in a major victory for Moldavia . Reasons for the war . After the Moldavian loss of Chilia and Cetatea Albă , the Ottoman threat seemed more evident . John Albert was suzerain of Moldavia , and , when Ştefan asked him for military assistance , they met , in 1494 at the conference of Levoča , where together with King Ladislaus II of Hungary and Elector Johann Cicero of Brandenburg , they forged plans for an expedition against the Porte . The objective was to recapture Chilia and Cetatea Albă . However , in unexplained circumstances , Ştefan received reports from Hungary that John Albert prepared to place his own brother , the Polish prince Sigismund ( later king , as Sigismund I the Old ) , on the Moldavian throne . Battle . By 1497 John Albert managed to gather 80 , 000 men and was preparing for the expedition when Ştefan invaded Galicia and pillaged it . The plans for the Ottoman invasion were put aside and John Albert went against Moldavia instead . The campaign started on the wrong foot , with John Albert entering Moldavia at Hotin and - despite sound advice to the contrary - deciding not to take the fortress , but to go straight for the capital city of Suceava . Later , this would prove a fatal mistake : by this time Stephen ' s scorched earth tactics were already common knowledge , as he had used it successfully several times before against the Hungarians and the Ottomans ; yet John Albert failed to secure his communication lines with Poland . Supply from home proved impossible and the Poles were forced to live off an already depleted land . After the abortive siege of Suceava ( September 26 - October 16 ) - with the taking of the recently rebuilt and reinforced fortress nowhere in sight ( despite having used heavy siege artillery on its walls ) , and facing famine , disease , bad weather plus the prospect of coming winter - John Albert was compelled to lift the siege . After some negotiations , the Poles left Suceava on October 19 ; apparently Stephen had granted them safe passage " on the condition that they return to Poland on the same way they had taken when marching on Suceava " and warning that he will not allow another part of his country to be devastated by the Polish troops in their retreat . John Albert formally accepted this condition ; however , in practice , he decided to retreat on a different and unfamiliar route through Bukovina to Sniatyn , instead of taking the route to Cameniţa through Hotin , knowing fully well that abiding by Stephen ' s condition would have spelled death for the exhausted and starved Polish troops , as they already had devastated that region on their way to Suceava , in an attempt to keep the army supplied . Breaking the arrangement previously agreed upon proved to be the fateful mistake that Stephen was waiting for all along : on October 26 he ambushed the Poles while they were marching on a narrow road passing through a thickly wooded area known as " The Cosmin Forest " . Thus , John Albert was unable to deploy his forces , rendering the Polish heavy cavalry completely useless . The several phases of battle lasted for three days , with Stephen routing the invading army , which was forced to flee in disarray , harassed all the way by the forces of the prince . At the same time a Moldavian contingent intercepted on October 29 a hastily assembled Polish relief force and completely annihilated it at Lenţeşti . However , once back in open space , the Poles were able again to take advantage of their heavy cavalry , and that part of the remaining troops which managed to retain a measure of order and discipline succeeded in crossing back into Poland - despite a Stephen ' s last effort to engage the remnants of the king ' s army in a battle of annihilation when they were trying to ford the Prut river at Cernǎuţi .