Judah, the fourth son of Jacob and Leah, was born in Charan on the 15th of Sivan, of the year 2196 from creation (1565 BCE). He passed away on the same date 119 years later, in Egypt.
Judah took the leadership role both in selling Joseph into slavery and in the brothers' later attempts to find him and free him, and to protect Benjamin. On his deathbed, Jacob conferred the leadership of Israel upon Judah, proclaiming: "The scepter shall not depart from Judah, nor the legislator from between his feet, until Shiloh (the Moshiach) comes..." The royal house of David, as well as many of the great sages and leaders of Israel throughout the generations of Jewish history, trace their lineage to Judah.
Judah had five sons: Er and Onan, who died without children; Shelah; and his twins from Tamar, Peretz and Zerach. Their descendants formed the Tribe of Judah, the most populous and prestigious of the twelve tribes of Israel.
After the death of King Solomon in 797 BCE, the people of Israel split into two kingdoms: ten tribes formed the Kingdom of Israel in the north, with Shomron (Samaria) as the capital; only the tribes of Judah and Benjamin remained loyal to Solomon's son, Rechavam, and formed the Kingdom of Judea in the south, in the areas surrounding the capitol Jerusalem. Eventually, the Northern Kingdom was conquered by Assyria and the ten tribes living there were exiled and lost to the Jewish people; the inhabitants of Judea were also exiled (to Babylonia) but subsequently returned to the Holy Land and rebuilt Jerusalem and the Holy Temple. Over time, the terms "Judean" and "Jew"--which originally referred to a member of the tribe of Judah--became synonymous with "Israelite" and was used to refer to the descendants of all of Jacob's twelve sons--i.e., the Jewish people.
Links:
More on Judah
Reuben and Judah; a Contrast
On Leadership
On the essence of the Jewish leader
Shortly after midnight of the 15th of Sivan of 1927, the sixth Lubavitcher Rebbe, Rabbi Yosef Yitzchak Schneersohn (1880-1950), was arrested by agents of the GPU (Soviet Secret Police) and Yevsketzia ("Jewish section" of the Communist Party) for leading the underground network of rabbis, teachers and emissaries working to preserve and disseminate Jewish learning and observance throughout the Soviet Empire.
Link: The Rebbe's Prison Diary
Rabbi Yosef Yitzchak of Lubavitch
On Simchat Torah we dance with our feet, not with our heads.
We are celebrating the Torah, and the Torah is something we study with our heads. But we dance with our feet, not with our heads.
If we would dance with our heads, each one would dance a different dance, each in a different space, some with friends but not with others, some as lonesome souls.
One head is higher, one is lower, one is here on earth, the other in the clouds or beyond, and some minds know only their own space that no one else can know.
But we dance with our feet, and all our feet are here on the same earth—none higher and none lower. So now we can all dance as one, with one heart, as a single being.
Now there is no loneliness, only joy.