History of the Republic of Venice of the Sea" ceremony was established in this period. Orseolo died in 1008. Venice's control over the Adriatic was strengthened by an expedition by Pietro's son Ottone in 1017, by which time Venice had assumed a key role in balancing power between the Byzantine and Holy Roman Empires. During the long Investiture Controversy, an 11th-century dispute between Henry IV, Holy Roman Emperor and Pope Gregory VII over who would control appointments of church officials, Venice remained neutral, and this caused some attrition of support from the Popes. Doge Domenico Selvo intervened in the war between the Normans of Apulia and
Gulf of Valencia dominant crops. ln May 2011 the energy firm Cairn Energy obtained licenses to explore for oil and operate drilling rigs and oil platforms in in the Gulf of Valencia from the Spanish government. There are environmental concerns about offshore drilling here. Gulf of Valencia The Gulf of Valencia (, ), is a gulf or inlet of the western Mediterranean Sea, on the eastern coast of Spain. Its limits are the Cap de la Nau headland in the south, while the northern limit is diffuse: for some it is the Cape of Vinaròs; and for others it is the Ebre Delta.