Shiloh was founded in two stages in 1978.
On the 1st of the Hebrew month of Shvat, the first families arrived and two weeks later, on Tu B'shvat, the official founding ceremony took place.
Here's a scene from the first days -
And here's another -
And here's a snapshot, taken by Asher Korlich, at the founding ceremony:-
That's Rav Tzvi Yehuda Kook at the microphone. To his left at the dias (on the picture's right) is Dr. Israel Eldad and to his right is Rav Eliezer Waldman, Rav Dov Lior, Rav Moshe Levinger. Just to the left of Rav Tzvi Yehuda's hat at the center is Gershon Salomon.