Archimandrite Job Getcha offers the following history of the Paschal celebration we Orthodox now keep:
“The Christians of Rome waited for cockcrow to break the fast, while those in Alexandria did so from the evening of the previous day. Dionysius reviews the resurrection accounts in the gospels: ‘on the night of Saturday’ in Matthew, ‘in the early dawn while it was still dark’ in John, ‘at the first break of day’ in Luke, and ‘in the early morning, at the rising of the sun’ in Mark. Dionysius writes: ‘At what moment he was resurrected, none of them tells us clearly, but only that, late on Saturday night, at dawn of the first day of the week, those who came to the tomb did not find him there.’ Unable therefore to establish the precise time at which to break the fast, Dionysius concludes:
This being the case, we answer those who seek to determine the time, to within half an hour, or a quarter hour, when it is fitting to begin celebrating the resurrection from the dead of our Lord. Those who are in too much of a hurry, and who relax (the fast) even before the night has approached its midpoint, these we censure as faint-hearted and intemperate, for they end their race just a little before the goal, whereas as wise man has said: ‘it is not a small thing in life to miss the goal by a little.’ As for those who delay and wait for the longest possible time, persevering until the fourth watch, when the Lord, walking on the sea, appeared to those who were traveling by boat, we commend them as courageous and devotees of penitence. Those who, between these two extremes, ended the fast according to their internal disposition and their ability, let us not trouble beyond measure; for indeed, not even the six days of fasting that come before are kept equally or similarly- some let all six days go by without taking any food, while others allow only two days, others three, others four, others none. For those who have struggled greatly in spending days without food, and who are exhausted and almost faint, we excuse them for taking food a little earlier; while those who not only did not pass these days without food, but who did not fast at all or even feasted during the first four days, and abstained from food only on the last two days, that is, on Friday and Saturday, and think that they are doing something great and splendid if they keep the fast until dawn on Sunday, I think that such people did not struggle as hard as those who exercised themselves for many days.
Later the Council in Trullo (692AD) established that:
After having spent the days of the saving passion in fasting, prayer, and compunction of heart, the faithful should break the fast only at midnight on Holy Saturday, because the evangelists Matthew and Luke, one through the words ‘late in the night that follows Saturday’ (Mt. 28:1), the other through the expression ‘at early dawn’ (Lk. 24:1), specify the late hour of the night.
[…] In Greek practice, the priest leaves the sanctuary and distributes the paschal fire while singing: ‘Come and receive light from the unfading light, and glorify Christ who rose from the dead.’ This chant, found in the contemporary Typikon of the Great Church, reflects a practice that became common in the nineteenth century, and which is rooted in the tradition of Jerusalem, no doubt in connection with the miraculous paschal fire attested since the twelfth century.[…] The modern Typikon of the Great Church calls for the reading of the pericope from Mark 16, a custom that appeared in the nineteenth century. The ancient Typika say nothing about a procession.” (The Typikon Decoded, pps. 230-231, 233)