A gathering including entertainers Hozier and the Dublin Youth Choir helped to switch on the festive lights at a ceremony at Áras an Uachtaráin on Saturday evening.
The annual "tree-lighting ceremony" sees President Michael D Higgins and his wife Sabina invite people from around the country to mark the beginning of the Christmas season.
In his remarks at the event, President Higgins said it was important that Irish people remember the core meaning of Christmas – a continued obligation to offer hospitality, “welcome strangers into our midst”, and celebrate the joy that welcoming strangers brings.
"In contemporary times, it means reaching out a hand of friendship to those who have travelled to Ireland from far away countries, and have arrived on our shores in need of refuge and shelter," he said.
“In doing so we stand in solidarity with all those across the world who are forced to leave their homes and their friends in search of a life free from fear and danger.”
It was also a challenging time of year for those who might be living far away from their country of birth, who depend on the kindness of new friends and neighbours while marking Christmas abroad, he added.
“For most of us, it would be impossible to imagine Christmas Day without our families, the people with whom we have built so many Christmas traditions and who will always, in years to come, be central to our memories of Christmases past.”
The President noted it was a time of year when some must recall family members and friends no longer living.
“So this Christmas, as we light the Christmas tree in Áras an Uachtaráin, we will remember the bereaved who are finding this Christmas difficult; we will remember our new Irish community as they recreate precious family traditions here in their new homeland; we will think of those in our society who are homeless, marginalised or vulnerable; of all those who are sick or lonely or feeling sad or worried.”
He made a special mention of members of the Irish Defence Forces who will be absent from home this Christmas due to peace-keeping duties abroad, and members of emergency services who will work across the season.
Wishing those present a peaceful and happy Christmas, in Irish, he remarked: “Ba mhaith liom Nollaig shona, síochánta agus sábh oraibh go léir. Agus do na páistí anseo uilig, tá súil agam go mbeidh lúcháir agus áthas ag Daidí na Nollag díobh, agus go mairfidh an Nollaig seo in bhur gcuimhne sna blianta romhainn.”