President Michael D Higgins condemned the "horrifying revelations" of a mass grave in Tuam at an International Women's Day event at Áras an Uachtaráin.
He paid tribute to the "relentless work" of local historian Catherine Corless, saying it was "another necessary step in blowing open the locked doors of a hidden Ireland".
"We are challenged to consider how the reprehensible attitudes that were held towards so-called 'unmarried women' and so-called 'illegitimate babies' came to be held," he said.
President Higgins and his wife Sabina welcomed over 100 women from various communities to celebrate International Women's Day.
The President said "dark shadows" hung over the event as a result of the mass grave confirmed in Tuam last week.
"Shadows that require us all to summon up yet again a light that might dispel the darkness to which so many women and their children were condemned, and the questions left unanswered as we moved on," he said.
"All of society loses when gender inequality is not only allowed to occur but is allowed to reproduce itself.
"This happens when a silence prevails where it should have been broken.
"So many questions remain and I hope the commission of inquiry will serve to put the truth on the record in a way that respects the memory of these children, their families, and their mothers in particular."
President Higgins also welcomed the commission of investigation that will examine the alleged abuse of an intellectually disabled young woman known widely as 'Grace' at a foster home in the south east of the country.
The President also used the occasion to highlight the issue of domestic violence against women which he said "has to stop".
"Domestic violence is an outright negation of the dignity and the rights of women.
"Our collective journey towards the full enjoyment of women's rights will never be complete if those abuses of the gravest sort are tolerated, if silence is allowed to prevail around them," he said.
He said that men "must be engaged" on the issue in order for progress to be made.
"Our responsibility - as a society, and individually, as concerned citizens - is to use all the means at our disposal, not just to curb, but to end this cycle of destructive violence," he said.
The President also spoke out in sympathy of those affected by the house fire in Clondalkin as well as congratulating the Traveller community on its recent state recognition.