Ilok (Croatian pronunciation: [ǐlok])[3] is the easternmost town in Croatia forming a geographic salient surrounded by Vojvodina.

The town is home to a Franciscan monastery and Ilok Castle, which is a popular day trip for domestic and cross-border tourists.

In Croatian, the town is known as Ilok, in German as Illok, in Hungarian as Újlak, in Serbian Cyrillic as Илок and in Turkish as Uyluk.

In 12th and 13th centuries the market-town of Ilok was mentioned in documents under various names (Iwnlak, Vilak, Vylok, Wyhok, Wylak).

At the end of the 13th century, Hungarian kings gave the Vylak castrum to the powerful Csák noble family.

In the 13th and 14th centuries, Ilok was a capital of the semi-independent medieval state of Upper Syrmia ruled by Ugrin Csák.

On 17 October 1991 during the beginning of the Croatian War of Independence, non-Serbs fled as the Yugoslav People's Army led by Serb paramilitaries occupied the area, but spared it from destruction due to its rapid surrounding and occupation.

Ilok is underdeveloped municipality which is statistically classified as the First Category Area of Special State Concern by the Government of Croatia.

[9] Slovak Evangelical Church of the Augsburg Confession established the local parish in Ilok in 1864 with building serving a place of worship, a school and a teacher's apartment.

[10] Following the completion of the United Nations Transitional Administration for Eastern Slavonia, Baranja and Western Sirmium Slovak Cultural and Educational Association Ľudovít Štúr joined the Union of Slovaks in Croatia while local Matica slovenská was established on 18 December 1997.