I was intriqed by the idea of an earlier United Italy, in the underrated superpower thread, so have been doing some research,
{If I had worked this hard on my homework back in school .........

}
I came across the Republic of Pisa.
Between 1030 and 1035 Pisa went on to successfully defeat several rival towns in Sicily and conquer Carthage in North Africa.
In 1051-1052 the admiral Jacopo Ciurini conquered Corsica
In 1060 Pisa won their first battle with Genoa
In 1063 admiral Giovanni Orlando, coming to the aid of the Norman Roger I, took Palermo from the Saracen pirates.
At this time the Pisan Navy was allied with, and acting almost as the Norman Navy
By 1072 The Normans take control over Sicily, and start on Tunisa,
Pisa took the Tunisian city of Mahdia in 1088.
In 1092 Pope Urban II awarded Pisa the supremacy over Corsica and Sardinia, and at the same time raising the town to the rank of archbishopric
A Pisan fleet of 120 ships also took part in the First Crusade and the Pisans were instrumental in the taking of Jerusalem in 1099.the Pisan crusaders were led by their archbishop Daibert, the future patriarch of Jerusalem.
Everything is going good for the Pisans and the Normans.
1135: Jerba comes under Norman control.
One of the last cities resisting the Normans
1148: When Mahdia is conquered, the Normans bring an end to the Zirid dynasty.
At this point the Normans control all of Tunisia.
Then only 11 years later
1159: Almohads conquers Tunis.
1160: Mahdia comes under Almohad control, and central Tunisia is with this governed from Marrakech.
And
End of 12th century: Almohads establishes themselves in Tunisia under the leadership of Ibn Ghaniyya.
70 years of steady takeover and expanding control crashes to a end.
And I can't find anything on the Web explaining what happened.
?Anybody Know? ?Any speculation on what would have happened if Norman Sciliy had kept Tunisia.? ?Any other Comments.?
And Pisa's winning streak ended in 1284
The power of Pisa as an international power was destroyed forever by the crushing defeat of the navy at the Battle of Meloria against Genoa (1284), in which most of its galleys were destroyed and many of the mariners were caught as prisoners. In 1290 an assault of Genoese ships against the Porto Pisano caused its destruction.