Short answers, pulled from the story.
Julius Caesar dedicated the Temple of Venus Genetrix in 46 BC. This dedication occurred within the Forum of Caesar and served as a political statement of the Julian family's divine lineage. The temple was a central part of the Roman religious landscape where the goddess was honored as the mother of the Roman people.
The earliest Roman goddess bearing the name Venus was a native Italic deity of gardens, vineyards, and the fertile earth. Her original cults focused on the protection of crops and the fertility of the land without elaborate myths of birth. This native goddess began as a local spirit of the soil and a figure of agricultural abundance.
The Trojan hero Aeneas is the ancestor of the Roman people according to the myth of Venus Genetrix. Julius Caesar claimed Venus as his personal ancestor by weaving her into the bloodline of the Roman state through Aeneas. Aeneas fled to Italy after the fall of Troy and became the progenitor of the Romans.
The festival of Venus Genetrix was celebrated on September 26. This day was dedicated to the goddess and the Julian family within the Temple of Venus Genetrix in the Forum of Caesar. The Romans sought her blessing through elaborate rituals and sacrifices on this date.
Julius Caesar built the Temple of Venus Genetrix to assert his family's divine right to rule and elevate Venus from a garden goddess to the divine matriarch of the Roman people. The temple served as a symbol of the Julian family's divine lineage and their political necessity. This structure was a physical manifestation of the connection between the divine and the political.