Islamist Mohammed Morsi became the Arab world鈥檚 first freely elected president Saturday, taking the oath of office and turning the page on 30 years of dictatorship in Egypt under ousted dictator Hosni Mubarak.

Morsi promised a 鈥渘ew Egypt鈥 as he assumed the presidential role before the Supreme Constitutional Court and its 18 black-robed judges in the Nile-side seat built to resemble an ancient temple.

He becomes the fifth head of state since the overthrow of the country鈥檚 monarchy 60 years ago, and the first elected leader to assume office since Mubarak left office 16 months ago during a popular uprising.

鈥淲e aspire to a better tomorrow, a new Egypt and a second republic,鈥 Morsi said during a solemn ceremony shown live on state television.

鈥淭oday, the Egyptian people laid the foundation of a new life -- absolute freedom, a genuine democracy and stability,鈥 said the 60-year-old Morsi, a U.S.-trained engineer from the Muslim Brotherhood.

The Brotherhood is a fundamentalist group that has spent most of its 84-year existence as an outlawed organization harshly targeted by successive governments.

Morsi arrived at the court around 11 a.m. local time in a small motorcade as hundreds of police and soldiers guarded the building outside.

Several hundred people outside cheered as he arrived and again when he departed as the country鈥檚 new president.

鈥淓gypt today is a civil, national, constitutional and modern state,鈥 Morsi, wearing a blue business suit and a red tie, told the judges. 鈥淚t is a strong nation because of its people and the beliefs of its sons and its institutions.鈥

Morsi then headed Cairo University where he was to make his inauguration address.

He was given an official welcome by an army band that played the national anthem as he stood to attention.

While Morsi鈥檚 election and swearing in as president is a personal victory, he still has a powerful military to contend with that has assumed most constitutional powers.

Military ruler Field Marshal Hussein Tantawi attended the university ceremony.

When he arrived, Tantawi was greeted by the crowd chanting, 鈥淭he army and the people are one hand,鈥 from the hundreds gathered in the university's main lecture room.

Morsi took a symbolic oath on Friday in Tahrir Square, birthplace of the uprising, and vowed to reclaim presidential powers stripped from his office by the military.

But by agreeing to take the official oath before the court, rather than before parliament as is customary, Morsi is seen as bowing to the military鈥檚 will. That power play is expected to continue playing out over the weeks and months ahead.

Morsi's Friday speech in Tahrir Square was filled with dramatic populist gestures as he staked a claim to the legacy of the uprising.

Later he opened his jacket wide to show that he wasn鈥檛 wearing a bullet-proof vest.

鈥淚 fear no one but God and I work for you,鈥 he told the cheering supporters.

As he was leaving the podium, he pushed aside two army soldiers from his security detail to wave goodbye to the crowd.