The Konigswarters were from the town of Konigswart in Bohemia, near Marienbad. Now both in Czech Republic with different Czech names. The familiy's original name was Baruch. A Baruch moved to Furth in Germany and was most likely obliged to take a German name. He took the name "Konigswarter" as he was "from Konigswart." The name has no basis in "Cohen" as some suggest. The Jewish name was Baruch.
He founded a bank in Furth and his four sons, all with the last name Konigswarter, fanned out to major cities - Vienna, Paris and two cities in Germany. They all did extremely well as bankers, gaining fortunes and in some cases titles. There are streets named after the Konigswart family and buildings built by them. The Viennese line was considered to be the wealthiest Jews in the Austro Hungarian empire and had vast landholdings, art and wealth. They were bankers to the Kaiser. The Konigswarters intermarried a great deal - marrying cousins. They also married into all the most prominent Jewish banking families of Europe. Very few people with the family name Konigswarter survived WWII. Most were from the Parisian line. Descendents with other last names still exist.
The Baruch family that stayed in Konigswart were hoteliers. They built the New York Hotel in Konigswart in 1770, that still stands - in half ruins. It is reputed to be the site of the oldest Mikva/ritual bath in Bohemia. They went on to build hotels in Marienbad - several have the initials "EB" in their facades, for "Emil Baruch" - a very successful hotelier.