[Sidenote: Naval demonstration at Lisbon]
The excesses of Dom Miguel's followers in Portugal were followed by more serious international results. A series of wanton attacks upon foreign subjects in Lisbon called for outside intervention. English and French squadrons appeared in the Tagus. Lord Palmerston, the British Foreign Secretary, declared himself satisfied after Portugal had apologized and paid an indemnity to the British sufferers. The French admiral, unable to obtain quick redress, carried off the best ships of the Portuguese navy. The worst result for Dom Miguel was the foreign encouragement given to his brother, Emperor Pedro of Brazil, who was preparing an expedition against him in the Azores. Some of the best British naval officers and veterans of the Peninsular War were permitted to enlist under Dom Pedro's banner. Captain Charles Napier took charge of Dom Pedro's navy. In July a landing was made near Oporto, and that important city was captured by Dom Pedro's forces. Dom Miguel was constrained to lay siege to Oporto. Thus the civil war in Portugal dragged on.
The most formidable revolt of the year was that of Mehemet Ali, the Viceroy of Egypt, against his suzerain, Sultan Mahmoud of Turkey. The disappointing results of Egypt's participation in Turkey's war in Greece left Mehemet Ali dissatisfied. He considered the acquisition of Crete by Egypt but a poor recompense for the loss of his fleet at Navarino.
A quarrel with the Pasha of Acre, Abdallah, gave Mehemet Ali a chance for Egyptian aggrandizement in that direction. Egyptian forces under the command of Mehemet Ali's adopted son Ibrahim marched into Palestine and laid siege to Acre. That stronghold resisted with the same stubbornness that Bonaparte had encountered years before. The protracted struggle there gave the Sultan time to prepare an expedition wherewith to intervene between his warring vassals. He took the part of the Pasha of Acre. A proclamation was issued declaring Mehemet Ali and his son rebels. A Turkish army under Hussain Pasha entered Syria. The fall of Acre, while the relieving army was still near Antioch, enabled Ibrahim to throw his full force against the Turks. In the valley of the Orontes the two forces met. The Turkish vanguard was routed and the Turkish main column fell back on Aleppo, leaving Antioch and all the surrounding country to the Egyptians. The Pasha of Aleppo, won over by Mehemet Ali, closed the gates of his city against Hussain's disordered forces. The Turks retreated into the mountains between Syria and Cilicia. The Egyptians pursued. At the pass of Beilan a stand was made by Hussain. The fierce mountain tribes turned against him, and with their help Ibrahim won a signal victory over the Turks, on July 29. The retreat continued through Cilicia far into Asia Minor. After several months a new Turkish army under Reshid Pasha, Ibrahim's colleague in the siege of Missolonghi, advanced from the north. A pitched battle was fought at Konieh on the 21st of December. The Turks were utterly routed. The army was dispersed and Reshid himself was made a prisoner. The road to Constantinople now lay open to Mehemet Ali. Sultan Mahmoud was so alarmed that he turned to his old adversary, Russia, for help. General Muravieff was summoned to Constantinople and was empowered to make terms for Turkey with Mehemet Ali.