In 1846, she arrived in Munich, where she was discovered by and became the mistress of, Ludwig I of Bavaria. The rumour was, at the time they met, Ludwig had asked her in public if her bosom was real. To which her response was to tear off enough of her garments to prove it. She soon began to use her influence on the king and this, coupled with her arrogant manner and outbursts of temper, made her unpopular with the local population (particularly after documents were made public showing that she was hoping to become a naturalized Bavarian citizen and be elevated to nobility). Despite the opposition, Ludwig made her Countess of Landsfeld on his next birthday, 25 August 1847. Along with her title, he granted her a large annuity.
For more than a year, she exercised great political power, which she directed in favor of liberalism, against the conservatives and the Jesuits. Her influence became so great that the ultramontane administration of Karl von Abel was dismissed because that minister objected to her being made Countess Landsfeld. The students of the university were divided in their sympathies, and conflicts arose shortly before the outbreak of the revolutions of 1848, which led the king, at Lola's instigation, to close the university. In March 1848, under pressure from a growing revolutionary movement, the university was re-opened, Ludwig abdicated, and Montez fled Bavaria, her career as a power behind the throne at an end. It seems likely that Ludwig's relationship with Montez contributed greatly to the fall from grace of the previously popular king.
After a sojourn in Switzerland, where she waited in vain for Ludwig to join her, she made one brief excursion to France and then removed to London in late 1848.