Luther lived with Katie for 1 1/2 years before marrying her?

Here's a comment from one of Rome's defenders from a discussion board. The charge against Luther this time is in regard to his relationship with his wife, Katherina von Bora:

If Martin Luther did not suffer from severe bipolar manic-depressant illness with frank psychosis during his periods of mania, he would never have invented a purely formal definition of 'righteousness' that was evacuated of all moral content and inspired millions of others to settle for a sub-Christian notion of discipleship… Luther lived with his paramour for 1 1/2 years before marrying her. He was complicit in the bigamy of Philip of Hess. He encouraged gangs of thugs to invade convents and rape the nuns therein. [CARM boards 3/26/16]

Origin of the Myth
There are multiple charges in this comment, most of them typical of Rome's defenders. The comment though that was atypical was,  "Luther lived with his paramour for 1 1/2 years before marrying her." A "paramour" is "a lover, especially the illicit partner of a married person." This is old school Roman polemic, hearkening back to the sixteenth century when Rome's defenders where scandalized by a monk marrying a nun. I'm not sure if the person making this charge was using the term in the sense that Luther was married to the church (so his relationship was Katherine was illicit), or if the person was simply using a fancy term to sound intelligent. I'm going to assume the later. I searched the phrase and came up with some exact hits to various Internet forums (2010, 2011, 2012, 2016, 2016). It appears the person posting this comment either previously posted the same content elsewhere or is currently plagiarizing. I suspect the former, and not the later.

Where was this notion taken from? For this current defender of Rome, I'm not sure, nor did I come across any elaboration. The myth itself may have originally come from a contemporary of Luther's: Cochlaeus. Katherina von Bora was said to be promiscuous, and that Luther eventually married her after she lived with him for two years. (see here for details). The myth did survive all the way up to the twentieth century, though tempered. Father Patrick O'Hare refers to Luther and Katie as, "the Adam and Eve of the 'new gospel' of concubinage." In his book, The Facts About Luther, O'Hare stated:

It is well known that he was pretty generally and often openly accused by his enemies, both Catholic and Protestant, of extremely grave moral delinquencies. No doubt there was considerable exaggeration in the accusations brought against him, but it nevertheless remains true that many of his faults and failings against morality cannot be denied or gainsaid. As a matter of fact he was openly blamed for his well known and imprudent intimacy with Katherine Von Bora before his marriage and Melanchthon severely censured him for his lack of personal dignity, his loose behavior and coarse jests in the company of his intimates and even in the presence of the nuns he helped in violation of Germanic law to escape from their convents (p.317).

[I]n violating the laws of God and disregarding his vow of chastity by taking a partner unto himself, he committed an act of perfidy and his union, even from a legal standpoint, was no marriage. Katherine Von Bora was only his companion in sin and the children brought into the world through the unholy alliance were illegitimate children (p. 344).

O'Hare then goes on to elaborate by delving into letters written at the time, insinuating that Luther married von Bora to stop the gossip about their relationship (p.345-347). O'Hare states,

His remarks in the letter as to certain rumors no doubt concern suspicions which were cast upon Luther's relations with Bora before their marriage. His conduct with Bora previous to wedding her called forth from both friends and enemies severe and apparently well-grounded criticism. Luther himself admits that his marriage was hastened precisely because of the talk that went the rounds concerning him and Bora. Burgenhagen said that "evil tales were the cause of Dr. Martin's becoming a married man so unexpectedly." And Luther himself wrote to his friend, Spalatin, that "I have shut the mouth of those who slandered me and Katherine Bora." It is not proven that he was openly immoral with her before marriage, but it is certain that there was so much talk going on about his intimacy with the ex-nun, that he thought it advisable to marry her sooner than he had expected (p.347).

The Facts: Luther did Not Live with Katherine von Bora Before Marrying

In response: of the biographical information available, the bare facts are as follows:

1. April 1523, Katherina Von Bora escaped from a convent with a group of nuns.
2. The group of nuns temporarily stayed in the Wittenberg castle untill homes were found for them.
3. Katherina stayed at the home of Philipp Reichenbach and Lucas Cranach
4. Luther married Katherina on June 13, 1525.

Or, to go beyond the bare facts, here's testimony from Roman Catholic historian Hartmann Grisar:

Of the twelve who escaped from Nimbschen, nine, who were without resources, found a refuge in various houses at Wittenberg, while only three went to their relatives in the Saxon Electorate. To begin with, from necessity and only for a short time, the nine found quarters in the Augustinian monastery which had remained in Luther's hands, in which he still dwelt and where there was plenty of room; later they found lodgings in the town. Luther had to provide in part for their maintenance. Catherine von Bora was lodged by him in the house of the Town-clerk, Reichenbach. [source]

For a helpful biographical article, see Katharina von Bora, the Woman at Luther's Sideby Martin Treu (Lutheran Quarterly XIII, 1999).


Erasmus and Rumors on Luther's Marriage
There were a number of rumors surrounding Luther's marriage believed by some of Rome's defenders- especially that Luther had sexual relations with her before their marriage, and got her pregnant. The offspring was popularly believed to be the Antichrist. Rome's defenders even produced abusive satires about their marriage. In regard to Luther and Katherina, Erasmus passed along this witty comment , "If there is truth in the popular legend, that Antichrist will be born from a monk and a nun (which is the story these people keep putting about), how many thousands of Antichrists the world must have already!"  According to Richard Marius, Erasmus initially believed the popular rumor that Kathrine von Bora had given birth a few days after her wedding. On page 438 of Martin Luther The Christian Between God and Death (Cambridge, Belknap Press, 1999), Marius states:

His forecast that his enemies would reproach him was on the mark. Then and for centuries afterward Catholic antagonists had proof that all Luther had ever wanted was sex, and since he married a former nun, it seemed he had now lived out yet another of the bawdy stories told of nuns and monks lusting for one another. His most bitter foes crowed over the marriage in monotonous fury in print. Erasmus knew of it by October and wrote to friends ironically about it. He passed on the canard that Katherine had given birth to a child a few days after the wedding (10). By March 13 he had learned that the rumor was false, although he understood (correctly) that Katherine was now pregnant. He ruminated on the 'popular legend' that the Antichrist would be born to a monk and a nun- a tale probably circulating about Luther's coming child. If that prophecy were true, he said with bitter wit, 'How many thousands of Antichrists had the world already known!'(11) He expressed the wistful hope that marriage might make Luther more gentle, but by this time he had seen Luther's vehement On the Bondage of the Will, and he had given up all hope that Luther might moderate his language.

(10) October 10, 1525; EE no. 1633; 6:197-199.
(11) March 13, 1525; EE no. 1677; 6:283-284.

Here are specific comments from Erasmus:

The comments from Erasmus ultimately served as a defense for Luther. Bayle's Dictionary was a popular eighteenth century apologetic dispelling numerous myths on various theological figures. Bayle did an entry entitled, "Bora." (see this overview as well). Bayle use the testimony of Erasmus under point #F.