The worship of Attis dated back centuries in Phrygia (aka Anatolia= modern Turkey) before it was imported to Rome in 204 BCE. Roman writers mentioning the religion include: Lucretius (lived 98 - 54 BCE), Catullus (86 -40 BCE), Varro (116 - 28 BCE), and Dionysus Halicarnasensis (first century BCE).
Attis predated Christ. Before and during the years the Christian Gospels were written (from the reign of Claudius, 41 – 54 CE) the Festival of Joy, celebrated Attis' death and rebirth was celebrated yearly in Rome. A Christian writer of the fourth century CE, recounted ongoing disputes between pagans and Christians over the remarkable similarities of the death and resurrection of their two gods. The pagans argued that their god was older and therefore original. The Christians admitted Christ came later, but claimed Attis was a work of the devil whose similarity to Christ, and the fact he predated Christ, were intended to confuse and mislead men. This was apparently the stock answer -- the Christian apologist Tertullian makes the same argument.
1) Attis was born
of the Virgin Nana on December 25th.
2) He was both the Father and the Divine Son.
3) The Festival of Joy―the celebration of Attis' death and rebirth
On March 22 a pine tree was brought to the sanctuary of Cybele, on it hung the effigy of Attis. The God was dead. Two days of mourning followed, but when night fell on the eve of the third day, the worshippers turned to joy. "For suddenly a light shone in the darkness; the tomb was opened; the god had risen from the dead ...[and the priest] softly whispered in their ears the glad tidings of salvation. The resurrection of the God was hailed by his disciples as a promise that they too would issue triumphant from the corruption of the grave." [for more see Frazer, Attis, chapter 1]
4) Attis' worshipers ate a sacramental meal of bread and wine. The wine represented the pagan god's blood; the bread became the body of the savoir.
They were baptized in this way: a bull was placed over a grating, the devotee stood under the grating. The bull was stabbed with a consecrated spear. "It's hot reeking blood poured in torrents through the apertures and was received with devout eagerness by the worshiper...who had been born again to eternal life and had washed away his sins in the blood of the bull." [for more see Frazer, Attis, chapter 1]
5) Called "the Good Sheppard," the "Most High God," the "Only Begotten Son" and "Savior."
NOTE: Frazer's classic Adonis, Attis and Osiris is a good place to go for details.