There is "no doubt" the SNP is "winning the case for independence", Nicola Sturgeon has declared.
While the Scottish First Minister said that politically "these can seem like dark times", she added that "there is light and there is always hope".
Ms Sturgeon told the SNP conference in Aberdeen: "Progressive values are being fought for in Europe. Young people are taking a stand for their future. And for Scotland, the hope lies in becoming an independent nation. Be in no doubt about this. We are winning the case for independence."
However, Scottish Secretary of State Alister Jack has ruled out the UK Government's support of a second independence referendum.
Ms Sturgeon declared: "It is time to take charge of our own future. It is time for independence."
But the SNP leader insisted her party would not win independence "the Brexit way", saying they would not resort to tactics such as "undermining democracy, demonising those who disagree, and plastering lies on the side of a bus".
Instead she said: "We will win by inspiring and persuading."
The First Minster started her key note address to the conference with an attack on the "crude populism" of US President Donald Trump and UK Prime Minister Boris Johnson.
Ms Sturgeon declared: "What leaders like Boris Johnson and Donald Trump have in common is this - a belief that nothing should be allowed to stand in the way of their own self-interest. Not facts or evidence. Not the rule of law. Not democracy. In some cases, not even basic human rights. We oppose the politics of Johnson and Trump. But let us be clear today that we reject their methods too. Crude populism tramples on the rights of minorities and tears at the very fabric of our democracy."
On the subject of Brexit Ms Sturgeon said "broken promises" from Labour, the Conservatives and Liberal Democrats in the 2014 independence referendum were the reason why "Scotland faces removal from the European Union today".
While she said a no-deal Brexit would be "unthinkable" she added that "a deal of the type Boris Johnson is proposing would not be much better". His plans would take Scotland out of the EU, out of the single market and out of the customs union."
She added: "Let me make this absolutely clear today, SNP MPs will not vote for that - not now, not ever."
Ms Sturgeon continued: "What makes Brexit so much worse for Scotland is that it is happening against our will. One of the sticking points in the negotiations with the EU has been the issue of consent for Northern Ireland. If there is to be a deal, it seems inevitable that it will include a process to allow Northern Ireland to decide if and for how long it will stay aligned to the single market and customs union. And that's exactly as it should be.
"But think about what that will mean. Wales will have voted to leave. England will have voted to leave. Northern Ireland will be given a say over its future. Scotland will be the only country in the UK to be taken out of the EU against our will and with no say over our future relationship with Europe."
While she insisted Brexit was a "disaster" she added it was a "symptom of a deeper problem".
Ms Sturgeon said: "That problem is the Westminster political union. For Scotland, Brexit shows that the Westminster system is broken. And it is broken utterly beyond repair."
Ms Sturgeon insisted her government had a "cast-iron mandate for an independence referendum".
She added: "That fact is beyond doubt. But we don't just have a right to offer the people of Scotland a choice over their future. In the circumstances now Scotland faces, we have a duty to do so. And it is what we intend to do."
The First Minister went on to tell SNP activists: "Our job is not just to deliver a referendum. Our job is to deliver independence."
She said the vote "must happen next year" and said the party was getting ready.
Ms Sturgeon stated: "By the new year, we will have completed our legislative preparations. We are already working to update the independence prospectus. And I can confirm today that before the end of this year, I will demand the transfer of power that puts the legality of a referendum beyond any doubt."
Scottish Secretary and south of Scotland MP Alister Jack has told ITV Border that Westminster will say 'no' to a second independence referendum:
To see the full interview, watch last night's Representing Border