[1] After the Munich Pact, which weakened Czech lands to the west, Hungarian forces remained poised threateningly on the Slovak border.

They reportedly had artillery ammunition for only 36 hours of operations and were clearly engaged in a bluff but had been encouraged by Germany, which would have had to support it militarily if the much larger and better equipped Czechoslovak Army had chosen to fight.

Slovakia declared independence and requested that Germany provide protection from Hungary, whose forces were, Ribbentrop stated, gathering on the border, take even more land.

On the evening of 13 March 1939, Tiso and Ferdinand Ďurčanský met Hitler, Ribbentrop and Generals Walther von Brauchitsch and Wilhelm Keitel in Berlin.

With medical staff next to him Hácha signed the document uniting what remained of Czechoslovakia with Germany forming the Protectorate of Bohemia and Moravia and informed Prague about his decision.

However, Hungary was not satisfied with the border with Slovakia and, according to Slovak sources, weak elements of their 20th Infantry Regiment and frontier guard repulsed a Hungarian attempt to seize Hill 212.9 opposite Uzhhorod (Ungvár).

It enclosed a map of their proposal that shifted the frontier about 10 km (6 mi) west of Uzhhorod, beyond Sobrance, and then ran almost due north to the Polish border.

In addition to the demographic issue, Hungary also had another purpose in mind: protecting Uzhhorod and the key railway to Poland up the Uzh River, which was within view of the current Slovak border.

Thus, Hungarian forces in the western Carpatho-Ukraine began to advance from the River Uzh into eastern Slovakia at dawn on 23 March, some six hours before Ribbentrop countersigned the Treaty of Protection in Berlin.

In the south, around Michalovce, Štefan Haššík, a reserve officer and a local Slovak People's Party secretary, gathered a group of about four infantry battalions and several artillery batteries.

Further west, in the Košice – Prešov front (on which Hungary maintained an infantry brigade,) Major Šivica assembled a third Slovak concentration.

To the rear, a cavalry group and some tanks were thrown together at Martin, and artillery detachments readied at Banská Bystrica, Trenčin and Bratislava.

Despite the confusion caused by the hurried mobilization and the acute shortage of officers, the Slovak force in Michalovce had coalesced enough to attempt a counterattack by the next day.

[clarification needed] The road-bound armoured cars engaged the Hungarian pocket from the front whilst Slovak infantry worked round their flanks.

Soon, they forced the heavily outnumbered Hungarians to fall back from Závadka towards their main line on the River Okna/Akna, just in front of Nižná Rybnica.

The armoured cars continued down the road a little past Závadka whilst the Slovak infantry fanned out and began to deploy on a front of some 4 km (2.5 mi) on either side of them, between the villages of Úbrež and Vyšné Revištia.

The Slovaks had advanced across open ground to within a kilometre of the Akna River when they began taking fire by Hungarian field and antitank artillery.

The raw infantry, unfamiliar with their new officers, first went to ground and then began to retreat, which soon turned into a panic that for some could not be stopped before Michalovce, 15 km (9.3 mi) to the rear.

Late on 24 March, four more OA vz.30 armoured cars and three LT vz.35 light tanks and a 37mm antitank cannon arrived in Michalovce from Martin to find total confusion.

However, the anti-tank section mistakenly drove past the knocked-out armoured car and ran straight into the Hungarian line, where it was captured.

[4] Many pilots flying together were then from different parts of Slovakia and had no time to train together, which put them at a marked disadvantage against the prepared and complete Hungarian squadrons.

Occupation of Spišská Nová Ves airport at 22 March 1939:[4] Other elements of the 3rd Air Regiment of Milan Rastislav Štefánik were at airfields in Vajnory, Piešťany, Nitra, Žilina and Tri Duby.

[clarification needed] Hungary concentrated its aerial assets on targets in eastern Slovakia:[5] The best plane in the Royal Hungarian Air Force was the Fiat CR.32 fighter.

On the morning of 23 March, two Slovak patrol squadrons operating from Spišská Nová Ves searched for the enemy, but the missions were not yet coordinated with ground units.

The second, also sent to Ulič, successfully destroyed a few Hungarian vehicles and damaged more equipment, but one plane was shot down and its pilot, Ján Svetlík, killed.

Most of the Hungarian bombs missed the air operations base, but several hit the airfield, a storage facility, a hangar, a brickworks and a barracks yard.

After the bombing of Spišská Nová Ves, Major Ján Ambruš arrived there on 25 March to organize a revenge air strike on Budapest, but the war ended before that could be carried out.

As a result, by a treaty signed on 4 April in Budapest, Slovakia was forced to cede to Hungary a strip of eastern Slovak territory (1,697 km2, 69,930 inhabitants, 78 municipalities), corresponding today to the area around the towns of Stakčín and Sobrance.