There were no dancers, no pyrotechnics and the only outrageous part of her outfit was the outsized golden brooch in the shape of a dove of peace (the colour matched her microphone and earpieces, lest you thought the whole ensemble was just thrown together).
That put the focus on her vocals, which were strong and assured, as she glided through the notoriously wide-ranging melody and its tricky vocal leaps.
Gaga, a vocal critic of the Trump administration, tweeted shortly before the ceremony that she wanted her performance to provide a moment of coming together after the divisions of the last four years.
"Singing our National Anthem for the American People is my honour," she wrote. "I will sing during a ceremony, a transition, a moment of change - between POTUS 45 and 46. For me, this has great meaning.
"My intention is to acknowledge our past, be healing for our present, and passionate for a future where we work together lovingly. I will sing to the hearts of all people who live on this land."