Czech Republic–Slovakia relations
Before 1918, both countries were part of Austria–Hungary. However, after the Ausgleich of 1867 Czechia belonged to the Austrian Empire while Slovakia belonged to the administratively separate Kingdom of Hungary, and between 1918 and December 31, 1992, both countries were part of Czechoslovakia. 
Both countries established diplomatic relations on January 1, 1993. These international relations are usually referred to or described as "very good", "cordial", and "above standard" in the media. When a Czech or Slovak president is inaugurated, very often his first international visit is to the former part of the common country. The same custom applies to newly elected prime ministers of the Czech Republic and Slovakia.
Slovaks
The territory of present-day Slovakia was split in two parts between the Kingdom of Hungary (under Hungarian rule gradually from 907 to the early 14th century) to Upper Hungary and Royal Hungary (under the Habsburgs from 1527 – 1848 (see also Hungarian Revolution of 1848)) until the formation of Czechoslovakia in 1918. However, according to other historians, from 895 to 902, the whole area of the present-day Slovakia became part of the rising Principality of Hungary, and became (without gradation) part of the Kingdom of Hungary a century later. A separate entity called Nitra Frontier Duchy, existed at this time within the Kingdom of Hungary. This duchy was abolished in 1107. The territory inhabited by the Slovaks in present-day Hungary was gradually reduced.