on Ibsen's character was sudden and it was final:

Then he stood up, and trod to dust
Fear and desire, mistrust and trust,
And dreams of bitter sleep and sweet,
And bound for sandals on his feet
Knowledge and patience of what must
And what things maybe, in the heat
And cold of years that rot and rust
And alter; and his spirit's meat
Was freedom, and his staff was wrought
Of strength, and his cloak woven of thought.

We are not left to conjecture on the subject; in a document of extreme
interest, which seems somehow to have escaped the notice of his
commentators, the preface to the second (1876) edition of _Catilina_, he
has described what the influences were which roused him out of the
wretchedness of Grimstad; they were precisely the revolution of
February, the risings in Hungary, the first Schleswig war. He wrote a
series of sonnets, now apparently lost, to King Oscar, imploring him to
take up arms for the help of Denmark, and of nights, when all his duties
were over at last, and the shop shut up, he would creep to the garret
where he slept, and dream himself fighting at the centre of the world,
instead of lost on its extreme circumference. And here he began his
first drama, the opening lines of which,

"I must, I must; a voice is crying to me
From my soul's depth, and I will follow it,"

might be taken as the epigraph of Ibsen's whole life's work.