Kaspar von Breitenlandenberg (died 24 April 1463 in Konstanz) was prince abbot of the Abbey of Saint Gall from 1442 to 1463. He descended from a noble family from the Canton of Thurgau. His father was Rudolf V von Breitenlandenberg (Landenberg).
Von Breitenlandenberg joined Reichenau Abbey in 1439, he took his religious vows there and then moved to Bologna to study canon law. After his return on 18 June 1442, he was appointed Abbot of Saint Gall by Pope Eugene IV. He received the bishop consecration on 24 September of the same year. Von Breitenlandenberg was considered a very educated man and was highly esteemed among the nobility. Thus, he became one of the presidents of the provincial chapter of the Benedictine order in Mainz and Bamberg. In later years, he held the office of treasurer of the chapter.
The city of Saint Gall, whose feudal lord Von Breitenlandenberg was, refused to pay him homage as he wanted to enforce old claims of ownership which the citizens were no longer willing to grant him. Emperor Frederick III, the Swiss people and several nobles were in the subsequent tedious dispute for the independence of the city alternately appealed to by both parties. On 17 August 1451, the abbot formed an eternally valid land law with the confederal cities of Zurich, Lucerne, Schwyz and Glarus. The lawsuit was only settled in 1457, however, thanks to the intermediation of Bern. The abbot was able to keep most of his rights, but the city had the possibility to buy them from him. On 14 May 1457, the city paid the amount of 7000 gulden and thus became a free imperial city. This was not the last of Kaspar von Breitenlandenberg’s trials, however. Already for quite some time, the monks of the abbey had accused him of mismanagement and agreements with the opposite party. His opinion regarding the rights of the city had in the course of the negotiations changed more and more in the city's favour, and eventually, he wanted to leave them all the sovereign rights of the monastery for only 1000 gulden, which, however, the convent was able to prevent. In November 1457, the abbot was definitely deprived of the administration of the abbey. The administration of finances had already been in the hands of his successor, Ulrich Rösch, for some time.
Von Breitenlandenberg spent the last years of his life chiefly in Reichenau or in Konstanz. He died on 24 April 1463 in Konstanz, but was buried in Saint Gall. During his reign, the convent counted more members than during the whole of the previous century.
The Abbey of Saint Gall is a dissolved abbey (747–1805) in a Catholic religious complex in the city of St. Gallen in Switzerland. The Carolingian-era monastery existed from 719, founded by Saint Othmar on the spot where Saint Gall had erected his hermitage. It became an independent principality between 9th and 13th centuries, and was for many centuries one of the chief Benedictine abbeys in Europe. The library of the Abbey is one of the oldest monastic libraries in the world.
Solomon III was the Bishop of Constance from 890 to his death. In 885, the Emperor Charles III made him archchancellor of the Empire, for Konstanz was then the greatest diocese in Swabia, which had been Charles' original kingdom and was still his home most of the time. As well as bishop, he was also abbot of Reichenau and Saint Gall, immensely powerful abbeys in Swabia. Solomon founded a church in honour of Saint Magnus at Saint Gall.
The Rorschacher Klosterbruch or St. Gallerkrieg was a war between the Abbey of Saint Gall, Zürich, Lucerne, Schwyz and Glarus against the city of St. Gallen and Appenzell in 1489 to 1490.
John II was the abbot of Saint Gall and of Reichenau and, from 760 to 782, was the Bishop of Constance.
Wolfleoz von Konstanz, or Wolleozzus was bishop of the Bishopric of Konstanz from 811 to 838/39 and abbot of the Abbey of Saint Gall from 812 to 816.
Gozbert was abbot of the Abbey of Saint Gall from 816 until 837 and also abbot of Rheinau Abbey until 850. The beginning of his term of office in Rheinau is unknown.
Werdo was abbot of the Abbey of Saint Gall in St. Gallen.
Ulrich von Sax was Abbot of Saint Gall from 1204 until his death.
Berchtold von Falkenstein was abbot of the Benedictine Abbey of Saint Gall from 1244 until 1272.
Eglolf Blarer was abbot of the Abbey of Saint Gall from 1426 to 1442.
Georg von Wildenstein was abbot of the Abbey of Saint Gall from 1360 to 1379.
Ulrich Rösch was abbot of the Abbey of Saint Gall from 1463 to 1491. He is considered one of the most outstanding abbots of the monastery.
Franz von Gaisberg was librarian from 1491 to c. 1496 and abbot of the Abbey of Saint Gall from 1504 to 1529.
Leodegar Bürgisser was abbot of the Abbey of Saint Gall from 1696 to 1717.
Cölestin II. Gugger von Staudach was from 23 March 1740 until his death prince abbot of the Abbey of Saint Gall. He is regarded as one of the most important abbots in the abbey's late period. He is attributed the solution of different long-lasting conflicts of the abbey, amongst others that with the Bishopric of Konstanz.The construction of the now world famous Saint Gall Cathedral was initiated and supervised by Cölestin, albeit he did not live to see its completion.
Bernhard Müller was prince-abbot of the Abbey of Saint Gall from 1594 until 1630. He was the son of Brosi Müller and Magdalena Lutz.
Beda Angehrn was prince-abbot of the Abbey of Saint Gall from 1767 until 1796.
Heinrich von Ramstein was abbot of the Benedictine Abbey of Saint Gall from 1301 until 1318.
Wilhelm I Count of Montfort was prince-abbot of Saint Gall from 1281 until 1301.
Heinrich von Wartenberg was anti-abbot of the Abbey of Saint Gall from 1272 until 1274.