This thesis examines the views of freedoms of press and speech held by the twelve earliest justices of the U.S. Supreme Court, as the Sedition Act of 1798 raised their earliest First Amendment questions including the breadth of those freedoms and of seditious libel. The thesis discusses three aspects of the early justices' views, which add to existing studies. First, the context of those justices' views was growing challenges to the restrictive Blackstone and Mansfield definition of freedom of press as only freedom from prior restraint (licensing) and as not also freedom from subsequent restraint such as seditious libel prosecution. Those challenges were reflected in broad language protecting freedoms of press and speech, and in the absence of language stating that the English common law of rights or of seditious libel was left unaltered. That crucial context of growing challenges has not been detailed in existing literature. (Chapter 3.) Second, the views of each early justice on press and speech are chronicled for the period 1789-1798. That discloses express commitments to those freedoms, which are absent from existing literature, and no adoption of the Blackstone definition before the 1798 crisis. (Chapters 4-5.) Third, the cases and reasoning of the six sitting justices upholding the Sedition Act of 1798 are chronicled and assessed, along with the views of the six remaining justices. That reveals that most remaining justices and also a significant minority within the Federalist party rejected the Sedition Act. Yet positions on the Sedition Act have been only cursorily discussed for four sitting justices and have been overlooked for the other eight justices, as well as for the Federalist party's minority, for the critical period 1798-1800. (Chapters 6-7.) The thesis proposes reasons for that divergence between the pre-1798 commitment of all justices to freedoms of press and speech, and the support given by most sitting justices to the Sedition Act, in contrast to apparent opposition by most remaining justices. The primary reasons are their opposing positions on several connected issues: the extent of rights to dissent, the challenges to the Blackstone definition and to seditious libel, the effect of new state and federal constitutions on seditious libel and on common law rights, strength of attachment to freedoms of press and speech and to seditious libel, and most sitting justices' changes of position to embrace the Blackstone definition. The thesis calls into question conventional views in existing literature on each of those three aspects. First, Levy and others express the dominant view that freedom of press in state declarations of rights and the First Amendment 'was used in its prevailing common law or Blackstonian sense to mean a guarantee against previous restraints and a subjection to subsequent restraints for licentious or seditious abuse,' so that contrary evidence 'does not exist,' and that 'no other definition of freedom of the press by anyone anywhere in America before 1798' existed. Instead, opposition to the essence of seditious libel had been mounting over the decades. Second, the early justices are usually portrayed as having nothing to say about freedoms of press and speech before 1798. Instead, nearly all exhibited commitment to those freedoms before that crucial year, though half the early justices upheld the Sedition Act during 1798-1800. Third, the Federalist party, the early justices, and the states except Virginia and Kentucky are all usually described as unanimously supporting the Sedition Act. Instead, the Federalists divided over the Act, and the early justices did as well, with an unrecognized but significant minority of the party, and nearly half of the early justices, opposing the Sedition Act, as did several additional states.