Question: Ivo Werner is from Country A that invaded Country B because their military branch that helped the Old West police was unprepared. When was the word "Slavs" used in the national anthem of country B?

Knowledge 1: Police
In the American Old West, policing was often of very poor quality.[citation needed] The Army often provided some policing alongside poorly resourced sheriffs and temporarily organized posses.[citation needed] Public organizations were supplemented by private contractors, notably the Pinkerton National Detective Agency, which was hired by individuals, businessmen, local governments and the federal government. At its height, the Pinkerton Agency's numbers exceeded those of the United States Army.[citation needed] [SEP] Knowledge 2: Josip Broz Tito
In 1968, Tito offered Czechoslovak leader Alexander Dubček to fly to Prague on three hours notice if Dubček needed help in facing down the Soviets. In April 1969, Tito removed generals Ivan Gošnjak and Rade Hamović in the aftermath of the invasion of Czechoslovakia due to the unpreparedness of the Yugoslav army to respond to a similar invasion of Yugoslavia. [SEP] Knowledge 3: Ivo Werner
Ivo Werner (born 19 August 1960) is a former professional tennis player originally from Czechoslovakia who competed for both his native country as well as West Germany. Werner, who is now a tennis coach, immigrated to West Germany in 1982 and got citizenship two years later. [SEP] Knowledge 4: Slavs
The word "Slavs" was used in the national anthem of the Slovak Republic (1939–1945), Yugoslavia (1943–1992) and the Federal Republic of Yugoslavia (1992–2003), later Serbia and Montenegro (2003–2006).
Knowledge 1: Police
In the American Old West, policing was often of very poor quality.[citation needed] The Army often provided some policing alongside poorly resourced sheriffs and temporarily organized posses.[citation needed] Public organizations were supplemented by private contractors, notably the Pinkerton National Detective Agency, which was hired by individuals, businessmen, local governments and the federal government. At its height, the Pinkerton Agency's numbers exceeded those of the United States Army.[citation needed] [SEP] Knowledge 2: Josip Broz Tito
In 1968, Tito offered Czechoslovak leader Alexander Dubček to fly to Prague on three hours notice if Dubček needed help in facing down the Soviets. In April 1969, Tito removed generals Ivan Gošnjak and Rade Hamović in the aftermath of the invasion of Czechoslovakia due to the unpreparedness of the Yugoslav army to respond to a similar invasion of Yugoslavia. [SEP] Knowledge 3: Ivo Werner
Ivo Werner (born 19 August 1960) is a former professional tennis player originally from Czechoslovakia who competed for both his native country as well as West Germany. Werner, who is now a tennis coach, immigrated to West Germany in 1982 and got citizenship two years later. [SEP] Knowledge 4: Slavs
Present-day Slavic people are classified into West Slavic (chiefly Poles, Czechs and Slovaks), East Slavic (chiefly Russians, Belarusians, and Ukrainians), and South Slavic (chiefly Serbs, Bulgarians, Croats, Bosniaks, Macedonians, Slovenes, and Montenegrins), though sometimes the West Slavs and East Slavs are combined into a single group known as North Slavs. For a more comprehensive list, see the ethnocultural subdivisions. Modern Slavic nations and ethnic groups are considerably diverse both genetically and culturally, and relations between them – even within the individual ethnic groups themselves – are varied, ranging from a sense of connection to mutual feelings of hostility.
Knowledge 1: Police
In the American Old West, policing was often of very poor quality.[citation needed] The Army often provided some policing alongside poorly resourced sheriffs and temporarily organized posses.[citation needed] Public organizations were supplemented by private contractors, notably the Pinkerton National Detective Agency, which was hired by individuals, businessmen, local governments and the federal government. At its height, the Pinkerton Agency's numbers exceeded those of the United States Army.[citation needed] [SEP] Knowledge 2: Josip Broz Tito
In 1968, Tito offered Czechoslovak leader Alexander Dubček to fly to Prague on three hours notice if Dubček needed help in facing down the Soviets. In April 1969, Tito removed generals Ivan Gošnjak and Rade Hamović in the aftermath of the invasion of Czechoslovakia due to the unpreparedness of the Yugoslav army to respond to a similar invasion of Yugoslavia. [SEP] Knowledge 3: Ivo Werner
Ivo Werner (born 19 August 1960) is a former professional tennis player originally from Czechoslovakia who competed for both his native country as well as West Germany. Werner, who is now a tennis coach, immigrated to West Germany in 1982 and got citizenship two years later. [SEP] Knowledge 4: Czech language
Around the sixth century AD, a tribe of Slavs arrived in a portion of Central Europe. According to legend they were led by a hero named Čech, from whom the word "Czech" derives. The ninth century brought the state of Great Moravia, whose first ruler (Rastislav of Moravia) invited Byzantine ruler Michael III to send missionaries in an attempt to reduce the influence of East Francia on religious and political life in his country. These missionaries, Constantine and Methodius, helped to convert the Czechs from traditional Slavic paganism to Christianity and established a church system. They also brought the Glagolitic alphabet to the West Slavs, whose language was previously unwritten. This language, later known as Proto-Czech, was beginning to separate from its fellow West Slavic hatchlings Proto-Slovak, Proto-Polish and Proto-Sorbian. Among other features, Proto-Czech was marked by its ephemeral use of the voiced velar fricative consonant (/ɣ/) and consistent stress on the first syllable.

Answer: 1943–1992