Irish immigrants in the early nineteenth century filled jobs created by the Market Revolution. Their arrival provided an important source of labor for a growing economy, but many Americans worried about the influence of these arrivals. Samuel Morse, an inventor who contributed to the development of the telegraph and Morse Code, feared that Irish immigrants represented the front line of a Catholic conspiracy to destroy the United States.

That a vigorous and unexampled effort is making by the despotic governments of Europe to cause Popery to overspread this country, is a fact too palpable to be contradicted. Did not official documents lately published, put this fact beyond dispute, yet the writer had personal evidence sufficient to convince him of the fact and of the political object of the enterprise, while residing in Italy in the years 1830-31, from conversations with nobles and gentlemen of different countries, with the officers of various foreign governments, visiting and resident in the Roman and Austrian states, and with priests and other ecclesiastics of the Roman faith. Sometimes it was hinted to him as a check to too sanguine anticipations of the triumph of the experiment of our democratic republican government; sometimes it was told him by the former class in a tone of exultation that a cause was in operation which would surely overthrow our institutions and gradually bring us under a form of government less obnoxious to the pride, and less dangerous to the existence, of the antiquated despotic systems of Europe. In addition to these hints to the writer, concerning the efforts making by the governments of Europe to carry Popery through all our borders, other American travellers will testify to similar hints made to them. By one I am permitted to say, that the celebrated naturalist, the late Baron Cuvier, known also as a zealous Protestant, inquired of him with marks of concern, if it were indeed true that Popery had made such progress in the United States, as to cause the exultation (which it seems was no secret) among the legitimates of Europe. And again, that a distinguished member of one of the Protestant German embassies, in Rome also made similar inquiries of him, having heard much boasting of the progress of Popery in the United States, adding this pertinent remark, “they will be hammer or nails, Sir, they will persecute, or be persecuted.” These facts may be of so much importance in aid of the other proofs of a conspiracy which these numbers unfold, as to show that among the various higher classes of Europe the enterprise of a Popish crusade in this country is not only a subject of notoriety, but is viewed with great interest, and is considered as having a most important political bearing…

Mistrust of all that Popery does, or affects to do, whether as a friend or foe in any part of the country, is the only feeling that true charity, universal charity, allows us to indulge….

Every account from Europe attests the correctness of the views here taken more than a year since, of the political state of the civilized world. This war of opinions, or of categories, as Lafayette termed it, is in truth commenced, and Americans, if they will but use common observation, cannot but feel that a neglect to notice, and provide against the consequences of that settled, systematic hostility to free institutions so strongly manifested by foreign powers, and which is daily assuming a more serious aspect, will inevitably result in mischief to the country, will surely be attended with anarchy if they wake not to the apprehension of the reality of this danger. Americans, you indeed sleep upon a mine. This is scarcely a figure of speech; you have excitable materials in the bosom of your society, which, skillfully put in action by artful demagogues, will subvert your present social system; you have a foreign interest too, daily, hourly, increasing, ready to take advantage of every excitement, and which will shortly be beyond your control, or will be subdued only by blood. You have agents among you, men in the pay of those very foreign powers, whose every measure of foreign and domestic policy has now for its end and aim the destruction of liberty every where. To increase your peril, you have a press that will not apprise you of the dangers that threaten you; we can reach you with our warnings only through the religious journals ; the daily press is blind, or asleep, or bribed, or afraid; at any rate, it is silent on this subject, and thus is throwing the weight of its influence on the side of your enemies. Foreign spies have clothed themselves in a religious dress, and so awe-struck are our journalists at its sacred texture, or so unable or unwilling to discern the difference between the man and his mask, that they start away in fear, lest they should be called bigoted or intolerant, or persecuting, if they should venture to lift up the consecrated cloak that hides a foreign foe. Americans, if you depend on your daily press, you rely on a broken reed; it fails you in your need. It dare not, no, it dare not attack Popery. It dare not drag into the light the political enemies of your liberty, because they come in the name of religion. All despotic Europe is awake and active in plotting your downfall, and yet they let you sleep, and you choose not to be awaked; “a little more sleep, a little more slumber, a little more folding of the hands to sleep.” And now like a man whose house is on fire, dreaming of comfort and security, you will perhaps repel with passion and reproach the friendly hand that would wake you in season to escape with your life.

Samuel Morse, Foreign Conspiracy Against the Liberties of the United States (New York: 1835), 16-18, 141-143.

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