Why doesn't Christianity accept reincarnation?

Although Eastern religions accept reincarnation as part of their doctrine, Christianity has rejected it since 553 AD, when it was dropped from their doctrine at the Fifth Ecumenical Council at Constantinople. At that time, the Roman Empire was divided into two parts: the Eastern Empire at Constantinople and the Western Empire at Rome. It has been noted historically that the rejection of reincarnation was personally motivated by Justinian, the Emperor of the Eastern Empire, and his wife, Theodora. Although the vote at the Council relied on bishops from both the Eastern and Western Empire, only two bishops from Rome came to Constantinople to vote. As two previous popes had been murdered after they denounced the dropping of the belief of reincarnation of the Bible, many of the Roman bishops were afraid to vote against the wishes of Justinian. After the vote, all Bibles were confiscated throughout both empires, burned and rewritten.

Below is an excerpt from the Fifth Ecumenical Council.

THE ANATHEMAS AGAINST ORIGEN

I.

IF anyone asserts the fabulous pre-existence of souls, and shall assert the monstrous restoration which follows from it: let him be anathema.

II.

IF anyone shall say that the creation (thu paragwghn) of all reasonable things includes only intelligences (noas) without bodies and altogether immaterial, having neither number nor name, so that there is unity between them all by identity of substance, force and energy, and by their union with and knowledge of God the Word; but that no longer desiring the sight of God, they gave themselves over to worse things, each one following his own inclinations, and that they have taken bodies more or less subtile, and have received names, for among the heavenly Powers there is a difference of names as there is also a difference of bodies; and thence some became and are called Cherubims, others Seraphims, and Principalities, and Powers, and Dominations, and Thrones, and Angels, and as many other heavenly orders as there may be: let him be anathema.

III.

IF anyone shall say that the sun, the moon and the stars are also reasonable beings, and that they have only become what they are because they turned towards evil: let him be anathema.

IV.

IF anyone shall say that the reasonable creatures in whom the divine love had grown cold have been hidden in gross bodies such as ours, and have been called men, while those who have attained the lowest degree of wickedness have shared cold and obscure bodies and are become and called demons and evil spirits: let him be anathema.

For the full doctrine go to Medieval Sourcebook: Fifth Ecumenical Council: Constantinople II, 553