The territory of the Republic of Ragusa from 1699 until 1806. The borders are equal to the modern southern tip of Croatia.
History
The fortified town of Ragusa might have already existed in ancient Greek or Roman times, but was first mentioned to be founded in 615 AD by Roman refugees from Epidaurus, a neighbouring town that was sacked by Slavs and Avars. At that time, Ragusa was part of the Byzantine Empire. It was at times shortly ruled by Venetians or Normans.
A failed attempt by the Republic of Venice to conquer the city in 948 was attributed to Saint Blaise (Sveti Vlaho), who became the patron saint of Ragusa and was depicted on Ragusa's flag and coins.
Flag of the Republic of Ragusa depicting Saint Blaise.
In the Middle Ages two towns existed separated by a canal, ome inhabited by Romans and one by Slavs. The latter was named Dubrovnik. In the 12th century the town was merged and both names were used. As Latin was the official language of the city's rulers the name Ragusa was preferred. In 1918 the city was renamed to Dubrovnik.
Venetian rule (1205-1358)
During the Fourth Crusade (1202-1204) the Byzantine Empire was severely weakened. Venice invaded and annexed Ragusa in 1205 and used the city as an important trading hub and naval base.
Hungarian suzerainty (1358-1458)
The Republic of Ragusa was established in 1358 as a vassal state of the Kingdom of Hungary, following the Treaty of Zadar which forced Venice to give up territories in Dalmatia. Apart from a yearly tribute paid to the King of Hungary the Republic of Ragusa was practically independent and established many trading routes between Western Europe and the Orient.
Ottoman protectorate (1458-1806)
The Ottoman advance in the Balkans and competition with Venice in maritime trade caused the Republic of Ragusa to accept Ottoman suzerainty in 1458. The tribute that had to be paid was large but Ragusa could continue to manage its own affairs, as long as it did not interfere with Ottoman interests.
In 1683, after the Ottomans were defeated near Vienna, Ragusa also started to pay tribute to the Hungarian King, who was also the Austrian Emperor. Ragusa therefore paid tribute to two neighbouring empires, allowing for unique trade routes.
Italy and the Dalmatian coast in 1789, showing Ragusa between Venetian Dalmatia and Venetian Albania (Cattaro/Kotor, presently in Montenegro).
Decline of the Republic of Ragusa
The oriental trade routes in the Mediterranean lost their importance from the start of the great Portuguese explorers who discovered new routes. An earthquake in 1667 destroyed a large part of the city.
The final blow to an independent Ragusa were the Napoleonic Wars, during which it was forced to side with one of the coalitions. To prevent a capture by the Russian fleet, the French took the city in 1806 and merged it with other formerly Venetian territories in the French Illyrian Provinces. With the defeat of Napoleon in 1814 Ragusa became Austrian. The Kingdom of Dalmatia was formed as one of the Austrian crown lands and existed until 1918.
Modern history (1918-date)
With the establishment of the Kingdom of Serbs, Croats and Slovenes in 1918 Ragusa was renamed to Dubrovnik, the Slavic name of the city that was already in use for centuries. Dubrovnik had a Croat majority and was part of the Independent State of Croatia during WW2 and the SR Croatia from 1945 to 1991.
During the early phase of the Croatian War of Independence (1991-1995) Dubrovnik was shelled by the Yugoslav National Army, inflicting damage to the old city. After Croatian independence in 1995 the damage has been repaired with help of international fund. Dubrovnik is a UNESCO site and attracts many visitors throughout the year. Much of the cultural legacy of Ragusa are still visible in Dubrovnik today.
Currency
From the 13th and 14th centuries until the 17th the Ragusan money system was based on the Denar (or Dinar, and Grosetto in Italian), which was a small silver coin and a common denomination throughout Medieval Europe. A Denar was equal to 6 Soldi (Solad) or 30 Minca (a small copper coin named Follaro in Italian). Minca's were minted until 1612. From 1627 to 1701 a silver coin named Artiluc (Artilucco, from Turkish Altılyq, piece of 6) was minted in Ragusa. One Artiluc equalled 3 Denar.
Starting from 1683 the main unit of account became the Perper, worth 12 Denar or 72 Soldi. The name of the Perper was derived from the Byzantine Hyperpyron, a gold coin from the 11th century. The Ragusan Perper was made of silver, with a weight of 5 to 6 grams.
In 1708 larger silver Scudo (Škuda) coins were introduced worth 3 Perpera. In 1723 this was followed by silver Ducats (Dukat) worth 40 Denar. From 1725 to 1779 versions of the Thaler (Tallero or Tolir) were minted with names such as Bradan or Vižlin. The Thaler was worth 5 Perpera.
Ragusa's last new denomination was the Libertine, worth 2 Ducats or 80 Denar. The Libertine had a legend with 'Libertas' (Liberty) on it, and was a large silver coin. It was minted from 1791 until 1795.
https://en.numista.com/catalogue/ragusa-1.html
But yes, Bohemian dukes and kings were lieges to German Kaisers, but with special status, and sometimes, Bohemian kings were even German Kaisers 
. Technicalities are long story, but Bohemia was rather independent from German States.