The Battle of Clontarf was also on a Good Friday. 1014, I think? Brian Boru died. Dante also entered the Dark Wood on a Good Friday, 1300, and in 1327 it was also the day the Francesco Petrarch saw his Laura and wrote:

It was the day on which the sun deprived of his light,
To rue Christ's death amid his course gave place unto night
When I amid mine ease did fall to such distemperate fits,
That for the face that hath my heart I was bereft my wits.
I had the bait, the hook and all, and wist not love's pretense,
But faired as one that feared no ill, nor forced for no defense.
Thus dwelling in most quiet state I fell into this plight,
And that day gave my secret sighs when all folk wept in sight.
For love that viewed me void of care, approached to take his prey,
And stepped by stelth from eye to heart, so open lay the way.
And straight at eyes broke out in tears, so salt that did declare
By token of their bitter taste that they were forged of care.
Now vaunt thee love which flee-est a maid defensed with virtues rare,
And wounded hast a wight unwise, unweaponed, and unware.

All in all, it is as Greg Orr said (about Petrarch, actually): "One more trapped man of the Renaissance looking for some way out that doesn't lead to God."