When is the First Communion for Children?
The month of May is the time of year when many second-graders receive their "First Communion." But it was not always so.
Until about the 13th century, children were admitted to communion from infancy. At baptism, infants were confirmed, and then given the Eucharist - usually a small amount of the consecrated wine. (The Eastern Rites have continued this practice down to the present day.)
Over the centuries, as disputes arose over the real presence of Christ in the Eucharist, the practice developed of requiring that children NOT receive communion until they had some instruction about the real presence.
In 1215, because Catholics by then received communion very infrequently, the Lateran Council decreed that all persons who had reached "the age of discretion" receive the sacraments of Penance and Eucharist at least once a year. (this came to be known as "the Easter duty.")
When applied to children, this meant that first communion was now delayed until they reached the age when they could have an understanding not only of the Eucharist, but of sin and forgiveness. This delayed receiving communion until the age of 10, 12, or even 14.
Seven centuries later, in 1910, Pope Pius X decreed that children should be admitted to communion as soon as they could distinguish between the Bread of the Eucharist and ordinary bread. Thus, First Communion was given at about the age of seven.
Source: Bishop Ken Untener, Little White Book, 2008.