In fact, since the time the Frisian territories had been part of the Frankish empire of Charlemagne, they had drifted away from mainstream European culture on a separate course, similar to that of the Swiss Confederation.

Across the Zuiderzee, which is today Lake IJsselmeer, lay the Frisian territories of Westergo and Oostergo (the borders of which approximately coincide with the present-day Dutch province of Friesland).

To the east the rich city of Groningen, nominally under the control of the bishop of Utrecht, but quite independent and very influential, was trying to develop its own sphere of influence in the Frisian lands.

When emperor Frederick Barbarossa travelled to the Netherlands in 1165, to settle the dispute between the counts of Holland and the bishops of Utrecht over the Frisian territories, he came up with a solution which was virtually guaranteed to keep things as they were.

When there was a weak bishop the influence of the count in the Frisian territories was greater, but usually still limited to the coastal region opposite Holland and the important trade city of Staveren.

Unlike William II and his predecessors, this time, Floris V did not attack West-Friesland from the south, but rather, he built a fleet, sailed around the coast, and came at his enemies from the rear.

Before the battle, a party of knights, led by William's uncle, John of Hainaut, Lord of Beaumont, went ashore south of Staveren, and captured the monastery of Saint Odulphus.

Shortly before 1396 though, there was a reconciliation between father and son, which was also meant to heal the rift between the Hoeks and Kabeljauws, promoting their newfound unity at home by making war abroad.

After the battle, Albert of Bavaria remained at Kuinre for a few more days, but, as Juw Juwinga had predicted, he found it very difficult to operate in the marshy terrain with an army of knights.

After 1396 the war at sea was resumed and in 1397 some small scale attacks were carried out on the Frisian coast at the city of Hindelopen and on the island of Terschelling, but these ended in débâcles.

The army, led by William of Ostrevant, landed without problems at Lemmer, and marched along the south coast of Friesland, which is sandy rather than marshy, to the city of Staveren.

After a violent skirmish negotiations were commenced, and William was offered a treaty by Gerard Camminga, Tsjerk Waltha, Heere Hottinga, Sjoerd Wiarda, Gotschalk Heslinga, Feye of Dokkum, and Tideman Hopper, the leaders of the Vetkoper party in Westergo and Oostergo.

Albert's solution was to ally himself with representatives of the Vetkoper party from the major Frisian territories between the Lauwers and the Ems: Hunsingo (Ayleko Ferhildema and Reyner Eysinga), Fivelgo (Omeko Snelgersma and Haye Wibben), and Oldambt (Tammo Gockinga and Menno Howarda).

Even further eastward he found allies in Widzel tom Brok and Folkmar Allena, who were at that time the most influential headlings in East Friesland, across the Ems, in what is today Germany.

This policy brought Albert in direct conflict with the powerful city of Groningen, which lay south of Hunsingo and Fivelgo, and southwest of Oldambt, and viewed these territories as her own backyard.

Then the Schieringers and Groningers together attacked the fortress at Ter Luine, but they were beaten back, mainly by the efforts of an English mercenary called Pantier, who single-handedly held a dam across a stream against them.

Officials appointed by the count were in fear of their life and could not let their guard down anywhere, as is shown by the fate of Simon van Zaanden, the steward of Oostergo and Westergo, who was murdered in the monastery (!)

The most important of these refugees were: Gerard Camminga, Feye of Dokkum, Renik of Sneek, Tsjerk Waltha, Gotschalk Heslinga, Galtke Aninga, Schelte Liauckama, and Bauwo of Sauwerd.

So the bishop stepped into the gap left by the retreating Hollanders, and allied himself with the Vetkopers in Hunsingo, Fivelgo and Oldambt, which led to renewed civil war in those territories, resulting in a resounding victory of the Schieringers, who were again supported by Groningen.

When the winter of 1410–1411 turned out to be so severe that travel across the Zuiderzee was made impossible by ice-drift, the Frisians decided to try to make use of the situation by trying to capture Staveren (which could not now be resupplied from Holland).

Under the terms of this truce Hollandic merchants got access to coastal towns and villages in Oostergo and Westergo from Dokkum in the northeast all the way around to Lemmer in the southeast; the Vetkoper refugees were allowed to return home; and William VI was awarded a large sum of money.

On 21 October 1413, the precarious balance of power in East Frisia (in what is today part of Germany) shifted, when the chieftain, Keno II tom Brok, captured the town of Emden.

The old rulers were exiled, and went to seek support from Keno tom Brok, who already had connections with some of the Vetkoper chieftains from Hunsingo, Fivelgo and Oldambt, the Ferhildema family among them.

Tom Brok captured Termunten, west of the Ems river, and became such a threat to Groningen, that church treasures were melted down to pay for a mercenary army to protect the city.

In 1416, a battle took place at Oxwerderzijl, close to the village of Noordhorn, in which the Schieringer force from Oostergo and Westergo, led by the chieftain, Sikke Siarda, was almost completely destroyed.

On 29 August 1419 the Schieringers, again led by Sikke Siarda, won a major victory over a Vetkoper army close to the city of Franeker, the capital of Westergo.

This led the Schieringers to openly start negotiations with John of Bavaria, who had defeated the Hoeks and had finally taken the countship of Holland, Zeeland and Hainaut in the previous year.

However, in 1420, the Hoeks, led by Philip of Wassenaar, Viscount of Leiden, had risen again, this time with the support of bishop Frederik III of Blankenheim, and the cities of Utrecht and Amersfoort.

On 1 February a formal reconciliation was concluded between Ocko tom Brok, the town of Groningen, Oostergo, Westergo, Hunsingo, Fivelgo, and the small territories of Vredewold, Langewold, and Humsterland.

At the end of May a fleet from the cities of Groningen, Hamburg, and Lübeck sailed to Dokkum, and drove the privateers out, thus depriving John of this last foothold on Frisian soil.